US5911941A - Process for the preparation of thick-walled ceramic products - Google Patents
Process for the preparation of thick-walled ceramic products Download PDFInfo
- Publication number
- US5911941A US5911941A US09/058,903 US5890398A US5911941A US 5911941 A US5911941 A US 5911941A US 5890398 A US5890398 A US 5890398A US 5911941 A US5911941 A US 5911941A
- Authority
- US
- United States
- Prior art keywords
- ceramic
- composition
- microwave
- heating
- microwave energy
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000000919 ceramic Substances 0.000 title claims abstract description 346
- 238000000034 method Methods 0.000 title claims abstract description 151
- 230000008569 process Effects 0.000 title claims abstract description 123
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 239000000203 mixture Substances 0.000 claims abstract description 101
- 238000010438 heat treatment Methods 0.000 claims abstract description 97
- 239000000463 material Substances 0.000 claims abstract description 69
- 238000010304 firing Methods 0.000 claims abstract description 45
- 238000001035 drying Methods 0.000 claims abstract description 35
- 239000007789 gas Substances 0.000 claims abstract description 31
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims abstract description 28
- 239000000835 fiber Substances 0.000 claims abstract description 16
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910010271 silicon carbide Inorganic materials 0.000 claims abstract description 10
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims abstract description 7
- 238000001125 extrusion Methods 0.000 claims abstract description 7
- 229910052582 BN Inorganic materials 0.000 claims abstract description 5
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 claims abstract description 5
- 150000004767 nitrides Chemical class 0.000 claims abstract description 5
- 150000001247 metal acetylides Chemical class 0.000 claims abstract description 4
- 238000005245 sintering Methods 0.000 claims description 47
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 38
- NLYAJNPCOHFWQQ-UHFFFAOYSA-N kaolin Chemical compound O.O.O=[Al]O[Si](=O)O[Si](=O)O[Al]=O NLYAJNPCOHFWQQ-UHFFFAOYSA-N 0.000 claims description 27
- 239000005995 Aluminium silicate Substances 0.000 claims description 26
- 235000012211 aluminium silicate Nutrition 0.000 claims description 26
- 239000004927 clay Substances 0.000 claims description 25
- 229910052570 clay Inorganic materials 0.000 claims description 25
- 239000000843 powder Substances 0.000 claims description 22
- 239000002245 particle Substances 0.000 claims description 19
- 238000001816 cooling Methods 0.000 claims description 18
- 238000010521 absorption reaction Methods 0.000 claims description 16
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 claims description 16
- 238000002156 mixing Methods 0.000 claims description 16
- 229910052863 mullite Inorganic materials 0.000 claims description 16
- 239000000654 additive Substances 0.000 claims description 14
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 14
- 239000007788 liquid Substances 0.000 claims description 14
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 11
- 238000002347 injection Methods 0.000 claims description 8
- 239000007924 injection Substances 0.000 claims description 8
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 claims description 7
- 239000000395 magnesium oxide Substances 0.000 claims description 7
- 239000011029 spinel Substances 0.000 claims description 7
- 229910052596 spinel Inorganic materials 0.000 claims description 7
- 230000000996 additive effect Effects 0.000 claims description 5
- 230000002411 adverse Effects 0.000 claims description 4
- 239000005388 borosilicate glass Substances 0.000 claims description 4
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 3
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 2
- 229910052796 boron Inorganic materials 0.000 claims description 2
- 229940117975 chromium trioxide Drugs 0.000 claims description 2
- WGLPBDUCMAPZCE-UHFFFAOYSA-N chromium trioxide Inorganic materials O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 claims description 2
- GAMDZJFZMJECOS-UHFFFAOYSA-N chromium(6+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Cr+6] GAMDZJFZMJECOS-UHFFFAOYSA-N 0.000 claims description 2
- 229910044991 metal oxide Inorganic materials 0.000 abstract description 7
- 150000004706 metal oxides Chemical class 0.000 abstract description 7
- 239000000047 product Substances 0.000 description 58
- 238000012545 processing Methods 0.000 description 26
- 239000000126 substance Substances 0.000 description 26
- 229910010293 ceramic material Inorganic materials 0.000 description 25
- 229910052751 metal Inorganic materials 0.000 description 25
- 239000002184 metal Substances 0.000 description 25
- 238000004814 ceramic processing Methods 0.000 description 21
- 238000004519 manufacturing process Methods 0.000 description 19
- 238000009740 moulding (composite fabrication) Methods 0.000 description 19
- 238000000280 densification Methods 0.000 description 18
- 230000007423 decrease Effects 0.000 description 15
- 230000005855 radiation Effects 0.000 description 15
- 238000005516 engineering process Methods 0.000 description 13
- 239000001257 hydrogen Substances 0.000 description 13
- 229910052739 hydrogen Inorganic materials 0.000 description 13
- 230000003993 interaction Effects 0.000 description 13
- 239000002994 raw material Substances 0.000 description 13
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 10
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 10
- 230000008901 benefit Effects 0.000 description 10
- 238000005304 joining Methods 0.000 description 10
- 239000010451 perlite Substances 0.000 description 10
- 235000019362 perlite Nutrition 0.000 description 10
- 229910052500 inorganic mineral Inorganic materials 0.000 description 9
- 239000011707 mineral Substances 0.000 description 9
- 239000007787 solid Substances 0.000 description 9
- 239000002699 waste material Substances 0.000 description 9
- 229910052799 carbon Inorganic materials 0.000 description 8
- 230000000694 effects Effects 0.000 description 8
- 150000002500 ions Chemical class 0.000 description 8
- 239000000084 colloidal system Substances 0.000 description 7
- 239000008187 granular material Substances 0.000 description 7
- -1 mullite Chemical class 0.000 description 7
- 230000035515 penetration Effects 0.000 description 7
- 239000012071 phase Substances 0.000 description 7
- 229920003023 plastic Polymers 0.000 description 7
- 239000004033 plastic Substances 0.000 description 7
- 239000011148 porous material Substances 0.000 description 7
- 230000032258 transport Effects 0.000 description 7
- 229910018404 Al2 O3 Inorganic materials 0.000 description 6
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 6
- 230000008859 change Effects 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- 239000002131 composite material Substances 0.000 description 6
- 238000010276 construction Methods 0.000 description 6
- 239000011521 glass Substances 0.000 description 6
- 239000004615 ingredient Substances 0.000 description 6
- 239000000377 silicon dioxide Substances 0.000 description 6
- 238000009792 diffusion process Methods 0.000 description 5
- 238000009413 insulation Methods 0.000 description 5
- 230000007246 mechanism Effects 0.000 description 5
- 238000009768 microwave sintering Methods 0.000 description 5
- 239000002707 nanocrystalline material Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N titanium dioxide Inorganic materials O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- 239000002250 absorbent Substances 0.000 description 4
- 239000006096 absorbing agent Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 239000004020 conductor Substances 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 238000005336 cracking Methods 0.000 description 4
- 239000003989 dielectric material Substances 0.000 description 4
- 230000005684 electric field Effects 0.000 description 4
- 230000005284 excitation Effects 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 230000036571 hydration Effects 0.000 description 4
- 238000006703 hydration reaction Methods 0.000 description 4
- 239000012535 impurity Substances 0.000 description 4
- 230000014759 maintenance of location Effects 0.000 description 4
- 239000011819 refractory material Substances 0.000 description 4
- 238000007669 thermal treatment Methods 0.000 description 4
- 241000196324 Embryophyta Species 0.000 description 3
- 239000011449 brick Substances 0.000 description 3
- 239000011248 coating agent Substances 0.000 description 3
- 238000000576 coating method Methods 0.000 description 3
- 239000002920 hazardous waste Substances 0.000 description 3
- 238000000265 homogenisation Methods 0.000 description 3
- 238000003780 insertion Methods 0.000 description 3
- 230000037431 insertion Effects 0.000 description 3
- 238000011068 loading method Methods 0.000 description 3
- 230000007774 longterm Effects 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 239000000615 nonconductor Substances 0.000 description 3
- 230000010287 polarization Effects 0.000 description 3
- 238000003908 quality control method Methods 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 238000003860 storage Methods 0.000 description 3
- 206010000060 Abdominal distension Diseases 0.000 description 2
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 2
- 239000011157 advanced composite material Substances 0.000 description 2
- 238000003915 air pollution Methods 0.000 description 2
- 238000013459 approach Methods 0.000 description 2
- 208000024330 bloating Diseases 0.000 description 2
- 238000004364 calculation method Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 238000005265 energy consumption Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 235000013305 food Nutrition 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 239000010954 inorganic particle Substances 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000007791 liquid phase Substances 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 229910052573 porcelain Inorganic materials 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 239000010865 sewage Substances 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 150000004760 silicates Chemical class 0.000 description 2
- 239000002915 spent fuel radioactive waste Substances 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- 230000008961 swelling Effects 0.000 description 2
- 238000001931 thermography Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 238000000844 transformation Methods 0.000 description 2
- 230000008016 vaporization Effects 0.000 description 2
- 238000003911 water pollution Methods 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 238000004566 IR spectroscopy Methods 0.000 description 1
- 229910004865 K2 O Inorganic materials 0.000 description 1
- 229910004742 Na2 O Inorganic materials 0.000 description 1
- XOJVVFBFDXDTEG-UHFFFAOYSA-N Norphytane Natural products CC(C)CCCC(C)CCCC(C)CCCC(C)C XOJVVFBFDXDTEG-UHFFFAOYSA-N 0.000 description 1
- 235000010627 Phaseolus vulgaris Nutrition 0.000 description 1
- 244000046052 Phaseolus vulgaris Species 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000001133 acceleration Effects 0.000 description 1
- 230000004308 accommodation Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 150000004645 aluminates Chemical class 0.000 description 1
- 125000000129 anionic group Chemical group 0.000 description 1
- 238000000137 annealing Methods 0.000 description 1
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 239000012237 artificial material Substances 0.000 description 1
- 239000002956 ash Substances 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 229910001423 beryllium ion Inorganic materials 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000037237 body shape Effects 0.000 description 1
- 238000009435 building construction Methods 0.000 description 1
- 239000002775 capsule Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 239000003818 cinder Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 239000004567 concrete Substances 0.000 description 1
- 239000012611 container material Substances 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000009770 conventional sintering Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000001808 coupling effect Effects 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007865 diluting Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 235000013601 eggs Nutrition 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 239000008151 electrolyte solution Substances 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000004534 enameling Methods 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 239000010433 feldspar Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000003574 free electron Substances 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000011440 grout Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 238000007731 hot pressing Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000012994 industrial processing Methods 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 230000037427 ion transport Effects 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 229910052622 kaolinite Inorganic materials 0.000 description 1
- 238000003913 materials processing Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 239000011859 microparticle Substances 0.000 description 1
- 238000003801 milling Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000010813 municipal solid waste Substances 0.000 description 1
- 239000005445 natural material Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000010955 niobium Substances 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 229910052575 non-oxide ceramic Inorganic materials 0.000 description 1
- 239000011225 non-oxide ceramic Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 229910052574 oxide ceramic Inorganic materials 0.000 description 1
- 239000011224 oxide ceramic Substances 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 230000021715 photosynthesis, light harvesting Effects 0.000 description 1
- 239000002574 poison Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000002285 radioactive effect Effects 0.000 description 1
- 230000002829 reductive effect Effects 0.000 description 1
- 239000003870 refractory metal Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000000930 thermomechanical effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 238000009489 vacuum treatment Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 125000000391 vinyl group Chemical group [H]C([*])=C([H])[H] 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- RUDFQVOCFDJEEF-UHFFFAOYSA-N yttrium(III) oxide Inorganic materials [O-2].[O-2].[O-2].[Y+3].[Y+3] RUDFQVOCFDJEEF-UHFFFAOYSA-N 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/64—Burning or sintering processes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
- B28B1/08—Producing shaped prefabricated articles from the material by vibrating or jolting
- B28B1/087—Producing shaped prefabricated articles from the material by vibrating or jolting by means acting on the mould ; Fixation thereof to the mould
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B11/00—Apparatus or processes for treating or working the shaped or preshaped articles
- B28B11/24—Apparatus or processes for treating or working the shaped or preshaped articles for curing, setting or hardening
- B28B11/243—Setting, e.g. drying, dehydrating or firing ceramic articles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B13/00—Feeding the unshaped material to moulds or apparatus for producing shaped articles; Discharging shaped articles from such moulds or apparatus
- B28B13/04—Discharging the shaped articles
- B28B13/06—Removing the shaped articles from moulds
- B28B13/067—Removing the shaped articles from moulds by applying blows or vibrations followed by, or during, the removal of a mould part
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B3/00—Producing shaped articles from the material by using presses; Presses specially adapted therefor
- B28B3/20—Producing shaped articles from the material by using presses; Presses specially adapted therefor wherein the material is extruded
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B3/00—Producing shaped articles from the material by using presses; Presses specially adapted therefor
- B28B3/20—Producing shaped articles from the material by using presses; Presses specially adapted therefor wherein the material is extruded
- B28B3/26—Extrusion dies
- B28B3/2627—Extrusion dies using means for making hollow objects with transverse walls, e.g. hollow objects closed on all sides
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B7/00—Moulds; Cores; Mandrels
- B28B7/40—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material
- B28B7/42—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material for heating or cooling, e.g. steam jackets, by means of treating agents acting directly on the moulding material
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B7/00—Moulds; Cores; Mandrels
- B28B7/40—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material
- B28B7/44—Moulds; Cores; Mandrels characterised by means for modifying the properties of the moulding material for treating with gases or degassing, e.g. for de-aerating
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B3/00—Drying solid materials or objects by processes involving the application of heat
- F26B3/32—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action
- F26B3/34—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action by using electrical effects
- F26B3/343—Drying solid materials or objects by processes involving the application of heat by development of heat within the materials or objects to be dried, e.g. by fermentation or other microbiological action by using electrical effects in combination with convection
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
- F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path
- F27B9/26—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path on or in trucks, sleds, or containers
- F27B9/262—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path on or in trucks, sleds, or containers on or in trucks
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/30—Details, accessories or equipment specially adapted for furnaces of these types
- F27B9/3005—Details, accessories or equipment specially adapted for furnaces of these types arrangements for circulating gases
- F27B9/3011—Details, accessories or equipment specially adapted for furnaces of these types arrangements for circulating gases arrangements for circulating gases transversally
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/12—Travelling or movable supports or containers for the charge
- F27D3/123—Furnace cars
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D5/00—Supports, screens or the like for the charge within the furnace
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/38—Concrete; Lime; Mortar; Gypsum; Bricks; Ceramics; Glass
- G01N33/388—Ceramics
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B9/00—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity
- F27B9/14—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment
- F27B9/20—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path
- F27B9/24—Furnaces through which the charge is moved mechanically, e.g. of tunnel type; Similar furnaces in which the charge moves by gravity characterised by the path of the charge during treatment; characterised by the means by which the charge is moved during treatment the charge moving in a substantially straight path being carried by a conveyor
- F27B9/243—Endless-strand conveyor
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P40/00—Technologies relating to the processing of minerals
- Y02P40/60—Production of ceramic materials or ceramic elements, e.g. substitution of clay or shale by alternative raw materials, e.g. ashes
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S977/00—Nanotechnology
- Y10S977/70—Nanostructure
- Y10S977/773—Nanoparticle, i.e. structure having three dimensions of 100 nm or less
- Y10S977/775—Nanosized powder or flake, e.g. nanosized catalyst
- Y10S977/776—Ceramic powder or flake
Definitions
- the present invention relates to a novel microwave-assisted process for the preparation of ceramic products, preferably large-sized, thick-walled ceramic products.
- the process is particularly suited for the preparation of large sized, thick-walled ceramic containers for the transport, storage, long-term containment and environmental isolation of nuclear and other hazardous waste.
- the process of the invention can produce ceramic containers that overcome the technical limitations and high cost of metal dry cask encapsulation or using glass or ceramic immobilization techniques, which are currently used.
- the process of the invention is also applicable for producing any large size, thick-walled product that may be desired.
- it may be used to produce high voltage electrical insulators, food and chemical apparatuses, engine blocks, very large slabs of ceramics that may be used to provide an exterior curtain wall on buildings; or roof tiles, large tiles for interior walls and floors; or structures either in one piece or a minimum number of pieces that combine floor, walls and ceiling for bathrooms, kitchens and other sanitary facilities.
- large-sized ceramic plates that can be produced by the process of the invention, it is possible to substantially reduce the amount of skilled masonry work and tilesetting labor required to cover surfaces. This is desirable also in view of the declining skills of tilesetters.
- Ceramic sewage and drainage pipes have been produced from ordinary clay for about two hundred years. Those pipes have a length up to 2,500 mm. Sewage pipes also may have an inner diameter up to 1,100 mm as described in ASTM, Designation: C 1208M-94, "Standard Specification for Vitrified Clay Pipe and Joints for Use in Jacking, Sliplining, and in Tunnels".
- Vitrified clay pipes should be non-permeable for water solutions and be resistant and reliable for use in all possible combinations of aggressive organic and non-organic chemical hazards.
- these pipes are manufactured by conventional firing from conventional fire clay, shale, surface clay, or a combination of these materials.
- the firing of such large ceramic products requires long firing times with slow ramp up and down of temperature and considerable cost in conventional energy forms and consequential adverse effects on the environment.
- Ceramics have low thermal conductivity. Therefore, the speed of conventional ceramic processing or an increase in the temperature of the external heating is inversely related to the body volume of the ceramic product. The greater the body volume, the lower the rise in temperature per unit of time and the longer the firing process. Consequently there is lower energy efficiency and, correspondingly, higher processing cost.
- the use of conventional heating methods in the production of large ceramic items requires a considerable amount of time and money to decrease body thermal gradients during a very long firing process.
- U.S. Pat. No. 3,585,258, granted Jun. 15, 1971, describes a method of firing a ceramic article by microwave energy at a firing temperature higher than available from the exposure of the article to the microwave energy which comprises locating the article in such a position as to subject it to the microwave energy, locating a plurality of loose or divided particles of a lossy material selected from the group consisting essentially of ferrites, iron, iron ore, and carbon in a predetermined fixed relationship with the article, which on exposure to microwave energy, provides the required firing temperature to fire the article, emitting microwave energy to the lossy material to generate a multitude of arcs therethrough, thereby generating high refractory heat energy for firing the article.
- a lossy material selected from the group consisting essentially of ferrites, iron, iron ore, and carbon
- U.S. Pat. No. 4,147,911 granted Apr. 3, 1979, describes a method for sintering refractories which comprises mixing a group of dielectric refractory particles with 0.1 to 5% by weight of an electric conductor, in which the particle size of the electric conductor is not more than 10 times the skin depth of the conductor in the microwave region, forming the mixture and sintering the formed mixture thus obtained by means of microwave induction heating in a space surrounded by a metal wall.
- U.S. Pat. No. 4,771,153, granted Sep. 13, 1988, describes an apparatus for heating a ceramic by microwave power.
- the apparatus has a cavity resonator in which the ceramic is placed.
- the resonator is provided with a variable iris.
- the apparatus detects the temperature of the ceramic or other state of the ceramic, and adjusts the area of the opening in the iris in the resonator and the resonant frequency of the resonator according to a signal produced by the detection, in order to bring the resonator substantially into resonance and the degree of coupling to exactly or nearly unity.
- the apparatus adjusts its microwave power for these purposes.
- U.S. Pat. No. 4,880,578, granted Nov. 14, 1989 discloses a method for microwave sintering of materials, primarily metal oxides.
- Metal oxides that do not normally absorb microwave radiation at temperatures ranging from about room temperature to several hundred degrees centigrade are sintered with microwave radiation without the use of the heretofore required sintering aids.
- This sintering is achieved by enclosing a compact of the oxide material in a housing or capsule formed of an oxide which has microwave coupling properties at room temperature up to at least the microwave coupling temperature of the oxide material forming the compact.
- the heating of the housing effects the initial heating of the oxide material forming the compact by heat transference and then functions as a thermal insulator for the encased oxide material after the oxide material reaches a sufficient temperature to adequately absorb or couple with microwave radiation for heating thereof to sintering temperature.
- a microwave sintering system and method are provided for sintering of large and/or irregular shaped ceramic articles at microwave frequencies of at least 28 GHz in the hundreds of kilowatts power range in an untuned cavity.
- a 28 GHz, 200 kW gyrotron with variable power output is used as the microwave source connected to an untuned microwave cavity formed of an electrically conductive housing through an overmoded waveguide arrangement which acts in conjunction with a mode promoter within the cavity to achieve unexpected field uniformity.
- the part to be sintered is placed in the cavity and supported on a removable high temperature table in a central location within the cavity.
- the part is surrounded by a microwave transparent bulk insulating material to reduce thermal heat loss at the part surfaces and maintain more uniform temperature.
- the cavity may be operated at a high vacuum to aid in preventing arcing.
- the system reportedly allows controlled increased heating rates to provide rapid heating of a ceramic part to a selected sintering temperature where it is maintained by regulating the microwave power applied to the part.
- U.S. Pat. No. 5,010,220 granted Apr. 23, 1991, discloses a process and apparatus for heating bodies to high temperatures at high pressures.
- the process involves locating the body in a chamber capable of acting as a resonant cavity for microwave radiation of a predetermined frequency.
- the body is then irradiated in the cavity with microwave energy of the predetermined frequency for a time sufficient to raise the temperature of the body to a suitable high temperature.
- a fluid at high pressure is introduced into the cavity to pressurize the body.
- the process can be used for sintering and/or hot isotactic pressing of bodies made of ceramic powder and for similar purposes.
- the process involves the use of a microwave susceptor (i.e., a material that couples well with microwaves) as a means for generating heat in the material.
- a susceptor is chosen which is converted, during the heating step, to a substance which is substantially the same as the material itself, both the susceptor and the material are converted to the same desired final product, or the material is converted to a substance substantially the same as the susceptor.
- the resulting substantially heat-treated (and preferably sintered) bodies can be used for a variety of purposes, e.g., as substrates for micro-electronic devices.
- the process can also be used for joining bodies of nonsusceptor materials.
- a ceramic article is coated with layers of protective coatings such as boron nitride, graphite foil, and niobium.
- the coated ceramic article is embedded in a container containing refractory metal oxide granules and placed within a microwave oven.
- the ceramic article is heated by microwave energy to a temperature sufficient to sinter the ceramic article to form a densifed ceramic article having a density equal to or greater than 90% of theoretical density.
- U.S. Pat. No. 5,202,541, granted Apr. 13, 1993 discloses a method of heating a workpiece assembly and a load assembly suitable for heating by the method.
- the method involves heating the workpiece assembly in a microwave cavity surrounded by one or more rings made of electrically conductive material.
- the rings fix the electrical field in such a way that uniform heating of the workpiece assembly can be achieved.
- Large workpieces or assemblies can be heated and, if sinterable, sintered in this way without the problems normally caused by lack of uniform fields when microwaves are used to heat large loads.
- U.S. Pat. No. 5,223,186 granted Jun. 29, 1993, describes a method of sintering nanocrystalline material wherein the nanocrystalline material is microwaved to heat the material to a temperature less than about 70% of the melting point of the nanocrystalline material expressed in degrees K.
- This method produces sintered nanocrystalline material having a density greater than about 95% of theoretical and an average grain size not more than about 3 times the average grain size of the nanocrystalline material before sintering.
- Rutile TiO 2 as well as various other ceramics have been prepared. Grain growth of as little as 1.67 times has resulted with densities of about 90% of theoretical.
- U.S. Pat. No. 5,321,223, granted Jun. 14, 1994 discloses a method of sintering a material with microwave radiation that comprises coating with microwave-absorbent carbon a compacted article comprising inorganic particles having poor microwave coupling characteristics at room temperature.
- the microwave-absorbent carbon does absorb microwaves at room temperature.
- the compacted article is irradiated with microwave radiation to heat the compacted article by microwave absorption of the microwave-absorbent carbon coated on the compacted article to a temperature sufficient for the inorganic particles in the compacted article to absorb the microwave radiation and for a period of time sufficient to sinter the compacted article and to remove the microwave-absorbent carbon coated on the compacted article.
- U.S. Pat. No. 5,365,042 granted Nov. 15, 1994 describes a heat treatment installation for parts made of a composite material having a ceramic matrix and including a treatment enclosure which is connected to a microwave generator by a waveguide and which includes a press for hot pressing a part to be treated in the enclosure and a gas source for introducing a protective gas into the enclosure.
- U.S. Pat. No. 5,521,360 granted May 28, 1996, discloses a variable frequency microwave heating apparatus designed to allow modulation of the frequency of the microwaves introduced into a furnace cavity for testing or other selected applications.
- the variable frequency heating apparatus is used in a method to monitor the resonant processing frequency within the furnace cavity depending upon the material, including the state thereof, from which the workpiece is fabricated.
- the variable frequency microwave heating apparatus includes a microwave signal generator and a high-power microwave amplifier or a microwave voltage-controlled oscillator.
- a power supply is provided for operation of the high-power microwave oscillator or microwave amplifier.
- a directional coupler is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity.
- a first power meter is provided for measuring the power delivered to the microwave furnace.
- a second power meter detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load.
- microwave furnaces are typically constructed with a fixed operating frequency. It has long been known that the interactions of various materials with microwaves are frequency dependent. These interactions may include sintering ceramics.
- U.S. Pat. No. 5,432,325 granted Jul. 11, 1995 discloses an apparatus and method for high temperature sintering of plate-shaped articles of alumina, magnesia, silica, yttria, zirconia, and mixtures thereof using microwave radiation.
- An article is placed within a sintering structure located within a sintering container which is placed in a microwave cavity for heating. The rates at which heating and cooling take place is controlled.
- UK Patent No. 2,296,173 (EA Technology Ltd.) describes a process for microwave-assisted processing of ceramic products.
- the process uses conventional heat sources if necessary to elevate the temperature of the ceramic products at which microwave energy is effective in heating the ceramic products and also to compensate for the heat lost from the surfaces of the ceramic product from the volumetric heat supplied by the microwaves.
- Yet another object of this invention is to provide a process that minimizes the time and the consumption of energy to produce the ceramic products and thereby maximizes the amount of products that can be produced in the process equipment per unit of time.
- the ceramic composition from the group consisting of silicate materials and other metal oxides, including mullite, alumina, red clay, magnesium aluminum spinel, as well as nitrides, carbides and mixtures thereof,
- ceramic fibers such as alumina, boron nitride or silicon carbide fibers
- composition so shaped to microwave energy to internally heat and thereby sinter the composition, optionally with external heat applied by means of electrical resistance or gas fired heating.
- FIG. 1 is a flow chart of a preferred embodiment of the process of the invention.
- FIG. 2 is a longitudinal cross-sectional view depicting the extrusion of cylindrical containers of large capacity.
- FIG. 3 is a longitudinal cross-sectional view depicting the vibrocompacting of containers of small to medium capacity.
- FIG. 4A is an end view of a microwave-assisted hybrid tunnel drier employing roller-induced conveyor movement of large cylindrical vessels and lids.
- FIG. 4B shows a longitudinal cross section of the microwave-assisted hybrid tunnel drier shown in FIG. 4A.
- FIG. 5 is a longitudinal cross-sectional view of a microwave-assisted hybrid tunnel kiln and an example of the corresponding temperature profile of the ceramic processing.
- FIG. 6 is a vertical cross-sectional view of a tunnel car used in the tunnel kiln shown in FIG. 5.
- a ceramic container vessel or its lid shown in cross section.
- FIG. 7 is a graph of experimental curves obtained by quantitative thermography of the dependence of the heat capacity of samples of perlite on temperature.
- FIG. 8 shows isolines of relative perlite granules additional weight, including granules which have been treated in an autoclave (except for hygroscopic liquid).
- the invention comprises an innovative and advanced ceramic technology for inexpensive and quality-controlled manufacturing processes for the production of unusually large-size and thick-walled ceramic products.
- FIG. 1 shows an over-all flow diagram of a preferred embodiment of the process of the invention, which can produce ceramic containers useful for the containerization of nuclear waste.
- Step 1 comprises batching of additives, plastificators, borosilicate glass, chromium trioxide and ceramic fibers and other additives. Ceramic fibers, whiskers or other fibers may be used. The additives may be present in total amounts up to about 20%. By “batching” is meant weighing out the ingredients to form a batch.
- Step 2 comprises the batching of fine powder ingredients for the basic ceramic composition, e.g., alumina powder, clay, kaolin, magnesium aluminum spinel.
- the particle sizes of the basic ceramic composition range from nanometers to a few mm. The actual optimal range of sizes is empirically determined for each ceramic component.
- Step 3 comprises batching of larger grain fractions of, e.g., magnesium aluminum spinel or alumina.
- the larger grain fractions may range in size to about 2 mm.
- Finely divided magnesium oxide lowers the sintering temperature of the ceramic composition.
- Another group of additives increases the plasticity of the ceramic mass, thereby making it possible to more readily form the desired ceramic product.
- the batch from Step 1 is then fed to a mixer where it is mixed with water in Step 4.
- the amount of water should be sufficient to mix, plastificate and form a homogeneous mass and yet not so much as to adversely increase the drying time.
- the amount of additional water or another polar liquid such as alcohol used may range up to about 18 percent of the total ceramic mass.
- Step 5 the batches from Steps 2 and 3 are mass mixed so as to be homogeneous.
- the mass is subjected to a steam autoclave treatment in Step 6 for a period of time sufficient to introduce hydrogen forms into the ceramic composition in an amount that serves to increase the absorption of microwaves during heating of the ceramic up to about 800 C.
- Step 7 the mass is subjected to a mix muller or attritor process. Then, depending upon the ceramic mass plasticity or whether one is preparing a container of a large capacity or a container of a small or medium capacity, the forming is conducted in alternative Step 8 or Step 9, respectively.
- containers of large capacity are preferably formed by extrusion forming of cylindrical vessels.
- Step 9 containers of small to medium size are preferably formed by vibrocompacting of, e.g., egg-shaped vessels. This may be seen in FIGS. 2 and 3. Either process of forming the containers may be used for producing the other type of container that is described above. Then the formed container from Step 8 or Step 9 is predried in Step 10 to form a green body. Preferably, the residual water in the ceramic is about 2%. In Step 11, the open ends of the container vessel and lid green body are machined to more precisely shape them.
- the machined green body is dried by means of microwave-supported (hybrid) drying, i.e., a combination of microwaves and conventional heating from either oil- or gas-fired or electric heaters, e.g., as shown in FIGS. 4A and 4B.
- the microwaves which may be in the range of a frequency of about 600 GHz to about 6000 GHz are preferably at a frequency of about 700 to about 4000 GHz and at a power level calculated based on the mass of the ceramic.
- the microwave energy is provided at a frequency of about 915 MHZ or 2450 MHZ.
- Step 13 quality control of the ceramic body is conducted. If a defect is discovered in a unit of the ceramic product, it may be recycled in the same process line. After that, in Step 14, the ceramic body is fired in a microwave-supported (hybrid) kiln, similar to the drying means described above in accordance with a thermal schedule, e.g., as shown in FIG. 5.
- Step 15 quality control of the ceramic products, e.g., container vessels and lids therefor, is conducted. The vessels and their lids are then assembled in Step 16.
- An auxiliary technology (Step 6) provides hydrogen insertion in ceramic particles, which are used during sintering.
- Ceramic mass formulation includes:
- the ceramic mass comprises one, two or more major components, such as preliminarily sintered and milled mullite or alumina or aluminum magnesium spinel or unmilled kaolin or clay or mixtures thereof in a range of about 80-100%.
- major components such as preliminarily sintered and milled mullite or alumina or aluminum magnesium spinel or unmilled kaolin or clay or mixtures thereof in a range of about 80-100%.
- the foregoing is a basic chemical and mineralogical composition.
- Other additives can be added in complementary amounts of from about 2 to about 20%, which with the basic composition total 100%.
- SiC is also a known susceptor (absorber) of microwave, which makes it possible to induce and accelerate microwave heating of ceramics during drying and firing stages of the production process.
- Another preferred additive is about 2-4% of a material which should decrease the sintering temperature of the material to 1300-1350° C., producing at these temperatures a liquid eutectic.
- An example of such an additive is borosilicate glass powder with a significant content of alkaline metal oxides. Additionally, boron increases nuclear retention and nuclear resistance properties of the ceramics.
- a similar effect may be furnished by carbon powder additive or carbon content materials, such as SiC, as a part of the ceramic green mass. This doping works as a susceptor of the microwave-ceramic interaction.
- a special grain fraction composition has been developed. To accomplish this, two fractions of ceramic raw materials are preferably used.
- the relatively coarse grain particles comprise about 63-67% of the fraction composition.
- the fine grain fraction should comprise about 23-25% of the fraction composition.
- the remaining portion of the fraction composition comprises nanophase or kaolin particles having a size which is less than about 60 nm. This grain composition makes it possible to achieve up to about 95-99% of the theoretical density of the ceramic material.
- Blending and other milling and mixing equipment provide mixing and homogenization of the raw composition that includes three to four types or more of powder and grain-size ceramic oxide raw materials, ceramic fibers (whiskers), and hot water.
- the mixing method which is described above, achieves necessary homogenization of the grain-powder mixture and less than 15% by weight of the mass as moisture, which is important to decrease heat consumption and time period of the drying process.
- additional mass blending may be coupled with a vacuum treatment.
- both ceramic vessel and lids are prepared at the same time and both of them are marked as two parts of a single container.
- FIG. 2 is a cross-sectional longitudinal view depicting the extrusion of a container 29.
- the auger 20 extrudes the ceramic mass 24 between cupping die 23 and kernel 25, which is held in place by pusher stock 28.
- the cupping-die 23 and the kernel 25 make it possible to produce cylinder-shaped vessels of containers with spherical bottoms or spherical lid-covers.
- the resilient curved underpan 30 receives the cylindrical container 29.
- the wire saw 22 is used to sever the cylindrical container 29 at the extruder outlet 21.
- a wire saw 22 is also used to trim the end of the cylindrical container 29 at its open end.
- Vibrocompaction is another method that may be used to produce a body shape for the container.
- a ceramic mass is loaded and compacted in a special form, using a vibrator in order to maximize density of the ceramic body.
- FIG. 3 is a vertical cross-sectional view depicting the vibromolding of a container of small to medium capacity.
- Ceramic mass 41 is placed in the space between water-permeable porous shell 43, which is contained in outside metal frame formed of at least four ribs 42, and water-impermeable inner shell 45, in which rests inner plastic rib frame 44.
- Vibrator frame box 48 is attached to outside metal frame 42, rests on vibration absorber 49, and houses vibrator 50. When activated, vibrator 50 compacts the ceramic mass 41.
- air valves 46 are opened and compressed air is introduced through openings in the inner plastic rib frame 44 and the water impermeable material 45 in order to release the inner plastic rib frame 44 and the water impermeable inner shell 45 from the formed ceramic mass 41, from which they are then removed.
- the whole vibromolding apparatus is contained within removable metal jacket (casing) 51, in the top of which is located a microwave waveguide inlet 52.
- Microwave waveguide inlet 52 serves to introduce microwave energy into the removable metal jacket (casing) 51. The microwave energy is used to predry and dry the ceramic mass 41 in the form of an egg-shaped container.
- the water released from the ceramic mass 41 during the predrying or drying step is removed from the removable metal jacket (casing) 51 by means of vacuum outlet 53.
- the removable metal jacket (casing) 51 is removed from the vibromolding apparatus.
- Pusher 47 is used to release the predried ceramic mass 41 in the form of an egg-shaped container.
- forming, predrying and drying processes are combined in one apparatus as shown in FIG. 3.
- the same form serves during a predrying process which is provided using microwave energy.
- the metal casing 51 protects personnel from microwaves.
- An outside wall of the container body is produced from porous water-permeable porous shell 43, which makes it possible to dry the ceramic.
- an inner surface of the form is produced from water-impermeable inner shell 45--see FIG. 3.
- An outside wall of the container form is produced with a few small holes. These holes make possible an air input between ceramic body and form wall to liberate ceramic body and remove this ceramic semi-product after drying process.
- a vacuum pump is employed, the outlet for which is shown as 53 in the FIG. 3.
- the microwave-assisted or hybrid drying process makes it possible to increase the efficiency of the drying process and the quality of the thick-walled product, providing precise control of the intensity of ceramic heating.
- heating of the ceramic body at about 20° C.-100° C. is provided by microwave energy.
- both hot gas/air mixture from a convection system and conventional electrical heater sources are employed together with microwave heat sources.
- FIGS. 4A and 4B Another and very effective construction of the dryer uses a roller conveyer for the horizontal movement of ceramic vessels and lids during thermal processing. This equipment achieves a high rate of productivity for industrial manufacturing--see FIGS. 4A and 4B.
- FIG. 4A is an end view of a microwave-assisted hybrid tunnel drier 60.
- Drying chamber 61 has a wall 62.
- the Bush roller chain 64 (seen in FIG. 4B).
- Elements of the electrical heaters 69 are used to supplement the heating provided by the microwave radiation.
- Blower fan 68 is used to provide a hydraulic thermal exchange circulation system, controlled by valves 68a-68f. Air is supplied to blower 68 by means of valve 68a. Blower 68 then delivers the air to drying chamber 61 via valves 68b to 68e. The heated air from the dryer is recycled to the blower 68 via valve 68f.
- FIG. 4B shows a longitudinal cross section of the microwave-assisted hybrid tunnel drier 60 shown in FIG. 4A employing roller-induced conveyor movement of large cylindrical vessels and lids 66.
- Drying chamber 61 has a wall 62.
- Bush roller chain 64 provides conveyor movement to rotating rollers 65 that bear, rotate and move ceramic cylinders 66.
- Microwave waveguide inlet 67 serves to introduce microwave energy through the wall 62 of the dryer 60. The microwave energy is used to dry the ceramic cylinders 66.
- the water released from the ceramic cylinders 66 during the drying step is removed from the drying chamber 61 by means of an outlet 110 in the wall 62 of the dryer that is remote from the microwave waveguide 67.
- Movement of a cylindrical ceramic item is provided in horizontal position by rotated rollers 65, using metal continuous chain 64.
- These rollers 65 are horizontally positioned and rotated in perpendicular direction of the ceramic vessel 66--FIG. 4B.
- the rollers 65 have a diameter size and a gap between two rollers 65 that are less than the diameter of the ceramic vessel 66.
- microwave energy sources in combination with electrical resistance heaters and/or gas burners and hot air-gas mixture which is supplied by the special hydraulic system permits thermally effective and uniform treatment of ceramic items in correspondence with an appropriate thermal-time schedule of the ceramic production.
- Microwave-assisted or hybrid firing increases the efficiency of the firing process and the quality of the product.
- Internal heating and sintering of the ceramic item body from 40° C. to 1350° C. is provided by microwave energy.
- Meantime, an appropriate heating of the thermal aggregate walls and the ceramic item surface is provided by the hot gas/air mixture that is delivered to the dryer and electrical resistance heaters and/or gas burners sources.
- FIG. 5 is a longitudinal cross-sectional view of a microwave-assisted hybrid tunnel kiln 70 and an example of the corresponding temperature profile of the ceramic processing.
- Tunnel kiln 70 has a multilayer wall 71 that includes refractory materials and a metal casing to prevent the escape of microwave radiation.
- the kiln cars 73 enter the tunnel kiln 70 from the left and ride on rail road 72.
- Microwave waveguides 74 serve to introduce microwave energy through the wall 71 of the kiln 70. The microwave energy is used to fire the ceramic containers assisted by electrical resistance heaters 82.
- Blower fan 75 uses a manifold for the hydraulic thermal exchange circulation system. Blower fan 76 uses a manifold for the hydraulic air-cooling circulation system. The hydraulic system is provided by blower fans 75 and 76 and chimney 77. Fan 76 blows outside air into the cooling zone 70c through multiple injection nozzles in the ceiling of the zone to surround the vessels 91. Some of the injection nozzles are aimed vertically downward and some of the nozzles are directed to provide air flow countercurrent to the travel direction of the vessels 91. Fan 75 takes hot air from the beginning of the cooling zone and delivers it to the heating zone 70a and the firing zone 70b. Outside air is taken in by fan 75 and used to control the temperature of the heating and firing zones, 70a and 70b respectively.
- Part of the heated air may be delivered to the dryer, which may be a separate unit. This method decreases energy consumption and increases the thermal efficiency of the system.
- the system serves to maintain the tunnel kiln at a pressure slightly below the atmospheric pressure for safety purposes and to decrease loss of heat.
- Chimney 77 exhausts the gaseous output of the kiln 70 assisted by chimney injector 78, which is fed by the manifold of the blower fan 75.
- the top of chimney 77 is covered by deflector 79 in order to prevent rain impact.
- Metal net curtains 80 are used to separate the cooling zone from the heating and firing zones, 70 and 70b, of the tunnel kiln 70.
- the ceramic containers enter the kiln 70 through metal door 81.
- Shown above the depiction of the kiln 70 is a profile of the temperatures at the different points within the kiln, ranging from 60 C at the entry point, rising to 600 C, then 1360 C, and falling to 300 C at the exit of the kiln.
- the kiln car 73 is shown in cross section in FIG. 6.
- a shuttle movement of the ceramic vessel 91 is provided by the kiln car 73.
- This car 73 has a ring-like refractory platform 99, which is capable of vertically rotating the ceramic vessel 91.
- Kiln car 73 transports ceramic vessel 91 through the tunnel kiln 70, where firing of the ceramic container vessel and its lid takes place.
- the tunnel car 73 has a metal base frame 92 on top of which is placed thermal refractory insulation 101 and to the underside of which are mounted metal wheels 93, which ride on rails 94.
- a ceramic container vessel 91 (or lid) rests on ground parts 100 of the refractory setting frame, which are joined to rotating dish-platform 99.
- a shaft passes through an opening in the metal base frame 92 of the tunnel car and extends between the rotating dish-platform 99 and revolving mechanism 98 to which it is joined.
- the revolving mechanism 98 is driven by electrical motor 97, which gets its power from an electrical current bar-rail source 95 by means of electrical contact brush 96.
- the kiln car has a ring-like refractory dish-platform and refractory frame setting which stabilize the ceramic item during car movement.
- a ring-like platform and setting frame of the car which bears the ceramic item is rotated by an individual electrical motor. Electrical current is taken by electrical contact brush from a current bar-rail which is positioned parallel to the rail road.
- Microwave energy is delivered by a few microwave guideways. They come through, for example, the ceiling of the tunnel in the area of the temperatures between 300° C. and a maximum temperature of the thermal processing.
- a uniform impact and a deep penetration into a ceramic body is achieved by a few other microwave sources at two or more different frequencies of the waves.
- the beginning part of the tunnel preferably has an inner metal screen-shell.
- This shell is preferably cooled by running water.
- a technique has been developed which prevents microwave--ceramic item interaction and heating of the ceramic item in the cooling zone of the kiln and makes possible air flow from the cooling zone to the sintering and heating zones.
- the technique comprises the use of one or a few removable and elastic metal nets 80 positioned within the tunnel 70. These metal net curtains 80 have small cell sizes and these cell sizes are less than half of the microwave wavelengths. These elastic metal net curtains 80 touch and slip off the ceramic items 91 on the cars as they travel through the tunnel.
- thermal aggregate is covered by a metal shell-jacket.
- one or both ends of the thermal aggregate are equipped with additional chamber rooms at both ends of the thermal aggregate, and each chamber has automatically closed doors whereby an open position of the outside door strictly corresponds to a closed position of the inside door.
- Both vessel and lid junction parts are machined for the first time after predrying in order to provide a necessary geometrical shape and a roughened surface of both clutched parts.
- Both vessel and lid joining surfaces are additionally machined to obtain a dense set of the micro and macro furrows and grooves which makes it possible to absorb the powder of the ceramic joining compound.
- Vessel and lid have one or more ring ridges and grooves on both joined ends of the container vessel and lid and these ridges and grooves completely coincide to produce a unified container.
- Each ridge and groove has in cross-sectional view either a triangular or trapezoidal form.
- the height of the triangular or trapezoidal ridges and the depth of the corresponding grooves may be up to one thickness of the ceramic wall of the container.
- FIG. 7 is a graph of experimental curves obtained by quantitative thermography of the dependence of the heat capacity of samples on temperature (the error in the determination of c p in the temperature range 300-1350 K is not higher than ⁇ 3%).
- c p heat capacity (cal/g deg)
- T temperature (K).
- Curve 1 represents a sample of the original perlite rock from Mukhor-Tallin location.
- Curve 2 represents the same sample after preliminary ignition at 1323 K.
- Curve 3 represents a sample of perlite, similar to the first sample, but thermally processed (swollen) under the following conditions of the first and second stages: 1) 603 K and holding time of 12 min, with removal of 2.65% of water; 2) 1323 K and 40 sec holding time.
- FIG. 8 shows isolines of relative additional weight of perlite granules, including granules, which has been treated in an autoclave (except for hygroscopic liquid):
- the hardening or sintering ceramic process is accompanied by volume variations which depend on the properties of the particular raw materials. These volume variations appear at appropriate temperatures and stimulate ceramic body stresses and volume shrinkage which create serious problems for ceramic processing, especially for articles having a large or precision shape.
- microwave energy is absorbed simultaneously throughout the work-piece (microwave heating acts internally within the bulk), microwave energy can provide uniform heating of the entire ceramic unit. As a consequence, microwave energy eliminates thermal gradients which produce stresses and cracking during heating, as may occur in conventional processing by external heating.
- microwave heating phenomena is the ability of microwaves to provide instantaneous penetration in the ceramic body which results in uniform ceramic body shrinkage during the densification and sintering processes. Uniform shrinkage of the ceramic mass permits the inexpensive production of large ceramic units. Microwave assisted (hybrid) internal ceramic heating presents a unique opportunity for ceramic technology to bring to the market new large (and specially shaped) products with special properties and at reasonable cost.
- microwave ceramic processing is the possibility of internally joining and sealing ceramic materials because of the transparency of the materials to microwave energy. Moreover, using appropriately processed powder, high temperature microwave heating can provide coating, covering, enameling, and glazing of ceramic and metal materials.
- a microwave tunnel furnace (kiln) may be fully controlled to provide a versatile and sensitive adaptation of the firing and cooling modes. All industrial processing can be done on a conveyer, which makes it possible to automate the technological operations of the forming, drying and firing stages.
- This invention employs a discovery that hydrogen forms and/or carbon that are present or are inserted in a ceramic micro and macro structure play an important role to induce, stimulate, and control microwave ceramic processing, depending on the chemical properties and physical conditions of oxide, carbide and nitride ceramics.
- the phenomena which have been discovered would also permit in-site joining of the ceramic parts (cup-vessel with a lid-cover) of multi-purpose container.
- the invention includes an advanced microwave furnace which comprises an industrial kiln to provide ceramic heating, sintering and joining of the container parts at 1200° C.-1600° C.
- Microwave thermal processing has the potential to be 15-30 times faster than conventional firing processes because ceramics can absorb more than 95% of the microwave energy delivered.
- any ceramic material may be used in the process of the invention.
- four types of ceramic materials are preferred as the most suitable materials. They are mullite (3 Al 2 O 3 ⁇ 2SiO 2 ), alumina (Al 2 O 3 ), magnesium aluminum spinel (MgAl 2 O 4 ), and red clay.
- the ceramic mass may also contain grain and powder additives, such as zirconia or borosilicate glass, and ceramic fibers, such as SiC and BN.
- the radionucleide accommodation, retention and radiation insulation properties of these materials increase from mullite to Synroc (CaZrTi 2 O 7 ).
- the production and raw materials costs of these products are increased by the same order with a tremendously increased factor for Synroc.
- red clay is the raw material of choice for the structural clay products industry. Ordinary clay is one of the more useful and inexpensive natural materials. The composition and properties of red clay vary with the nature of the deposit. A mixture of various silicate materials is mostly used for clay brick, roof tile, drainage and sewerage pipes and pottery products. Many types of clay have an excellent plasticity which permits easier forming processes.
- Kaolin is a type of clay which has an especially stable and homogeneous chemical and mineralogical composition.
- Kaolin mineral homogeneity is important for microwave firing because the uniformity of microwave heating depends on homogeneity of the ceramic starting materials.
- Kaolin based products include whiteware, china, electrical ceramics, refractories and composite engineering construction ceramics.
- An example of an advanced composite is a mullite matrix with boron nitride fibers.
- Kaolin is a relatively inexpensive natural material with lattice hydrogen content. It has a plasticity property and can absorb hydrogen forms through the surface and, accordingly, permits the use of extrusion and casting for forming processes.
- Kaolin is used in numerous ceramic applications where its refractive, Theological properties and fired whiteness are important. Kaolin is widely used for china, tile, chemical equipment, electrical insulators, and sanitary wares.
- the production of refractories from kaolin is a well-known technology.
- one U.S. kaolin deposit consists of 55.2% SiO 2 , 27.9% Al 2 O 3 , 12.6% of the weight (mainly "water”) is lost on ignition, and the remainder consists of the following oxides: TiO 2 , CaO, MgO, K 2 O, and Na 2 O. Sintering by conventional external heating occurs at about 1350° C. by the major reaction:
- Al 2 O 3 ⁇ 2SiO 2 has the form of mullite crystals which are homogeneously mixed with silica glass.
- Some types of kaolin have exceedingly small grain powder sizes. This powder may absorb large quantities of water which results in a swelling of the material and makes for a difficult forming process. Therefore, a mixture of kaolin with conventional clay and ignited kaolin is preferred as one starting material in the process of the invention. Ignited kaolin or preliminarily preformed mullite are inert to water and may substantially increase the forming property of the mixture. Additionally, ignited inert ceramic granules decrease body volume variations during low and high temperature thermal processing.
- Kaolin raw material can be a base to artificially produce (sinter) a mullite mineral.
- Kaolin is a well-known and widely used chemically and mineralogically homogeneous raw material with a reasonable low cost of mining and preliminary treatment.
- Mullite-content material embodies refractory and armor properties and it is used as a material that is resistant to mechanical, electrical, thermal and chemical stresses in extreme and aggressive technological situations, including some combination of them within a chemical reactor or a metallurgical vessel. Because it contains a substantial percentage of alumina oxide, mullite can retain and insulate radionucleides without a serious change of the chemical and mechanical properties of the initial material and unit shape during millions of years in any adverse conditions, including combined thermal-radiation impact.
- Adding other ceramic fibers to the ceramic body substantially increases the mechanical properties of a multi-purpose container material.
- the insertion of BN continuous fibers provides a superior composite material because BN is the best artificial material for nuclear retention and insulation, tensile strength, fire and electrical resistance and other chemical and mechanical properties.
- the aforementioned materials and compositions are selected and ranged in consideration of their costs and manufacturability when there are a lot of other ceramic materials.
- Table 2 compares the physical and mechanical properties of other ceramic and metal materials, and demonstrates that ceramic materials can have perfect mechanical and other properties which makes them suitable for a multi-purpose container.
- Table 2 also shows the greater compressive and tensile strength, fracture and crack resistance of ceramic materials in comparison with steel, especially by reason of the fact that at 300° C. the tensile strength of metals usually decreases by 1.7-2.0 times whereas mullite refractors and other ceramics have the same tensile strength as at room temperature.
- Alumina and kaolin materials and their fiber reinforced compositions may be selected and ranged in consideration of their costs and manufacturability when there are a lot of other ceramic materials.
- Table 2 compares the physical and mechanical properties of three ceramic materials and demonstrates that ceramic materials can have perfect mechanical and thermal properties, which make them suitable for a multi-purpose container.
- the process of the invention may be used to produce any ceramic products, particularly large-sized, thick-walled ceramic products, it is especially well suited to the production of multi-purpose containers. Therefore, the production of such products is emphasized herein. However, the specific description with respect to the production of multi-purpose containers is also generally applicable to the production of any other ceramic product.
- the multi-purpose container are preferably produced with two shapes of the container vessel, which depends on the shape, size and conditions of the loaded solid waste products:
- the inside and outside shapes of the container vessels and lids may be any combination of the spherical, ellipsoid and cylinder forms.
- An ellipsoid or spherical shape is preferred for the ends of the module size containers with a capacity in the range of 0.5 m 3 to 10 m 3 .
- Small and medium capacity containers are similar to eggs; whereas the large capacity containers have more or less length in a cylindrical part. This form permits uniform body variations caused by production processing of ceramic vessels and lids, their thermal joining and during thermal expansion due to radioactive heating. Also some small swelling may occur under long term radiation impact.
- the containers can be produced with different inner capacities, for example, small capacities from about 0.1 m 3 to about 0.75 m 3 , medium capacities in the range of about 1 m 3 to about 2.5 m 3 , and large capacities up to about 10 m 3 and more.
- the diameter size of the multi-purpose container which can be varied from about 250 mm to about 1200 mm permits the loading of large-size blocks or contaminated parts of other equipment into the multi-purpose container.
- the capacity of the multi-purpose container optimizes interim loading time when the multi-purpose container is used for other nuclear waste sources, directly at the site. Additionally, the shape and size of the multi-purpose container-package is determined by transportation and repository requirements.
- the wall thickness of the multi-purpose container should be in the range of about 60 mm to about 150 mm because these walls are a barrier for radionucleides and must withstand all possible mechanical impacts which may occur during transportation or in the repository.
- microwave ceramic processing is an especially environmentally clean technique and does not cause the air or water pollution that is produced by traditional ceramic and metallurgical plants.
- Broken and destroyed ceramic products can be returned to the same ceramic plant to be used as a part of the raw materials mixture.
- Table 3 below shows the benefit in energy expenditure from microwave ceramic processing. According to experimental data from this preliminary study, microwave ceramic processing can decrease the sintering-processing temperature by 100° C.-200° C. and reduce the processing period by 20 times.
- the capital cost to design, construct, produce and install a microwave conveyer kiln, machinery and equipment for ceramic mass preparation, forming, drying, firing, and product transportation is less than that of traditional kilns for structural clay products, electrical porcelain insulators or whitewares because of the elimination of thick refractory insulation shells and reduction of kiln length.
- the major part of ceramic technology which defines ceramics as an independent part of science and technique is the unconvertible densification as a result of thermal treatment. This treatment is often separated into two stages: drying and firing. Drying results in preliminary ceramic densification due mainly to adhesion of ceramic particles when the liquid binding (water, e.g., polar organic liquid) is removed.
- the main goal of ceramic drying is the preparation of shaped ceramics for loading and handling inside a ceramic kiln (furnace).
- Many technologies combine low and high temperature ceramic treatment in one aggregate. Low temperature drying can utilize the surplus heat of high temperature ceramic firing.
- the ceramic firing process is unique to the creation of ceramic materials and products. Firing produces ceramic sintering and stone-like densification. Sintering may involve a number of processes simultaneously, including diffusion, chemical interactions, melting and volumetric change, depending on the particular mineral composition employed. These characteristics are known in general and also for each isolated phenomenon. However, the sintering of ceramics is a multi-faceted process due to interactions between three phases: solid, liquid, and gas. These interactions involve chemical reactions, diffusion, mechanical movements of the particles, evaporation, and absorption. All of these actions are induced by a thermal stream. The speed and power of the heating, i.e., the thermal stream, determine the dynamics and kinetics of the sintering process. Therefore, ceramic thermal absorption can often describe the kinetics of ceramic densification and sintering processes.
- thermally activated processes must be accomplished, accommodated or avoided to provide ceramic processing.
- the same thermal cycle that causes positive densification and particle bonding also may lead to unexpected shrinkage and other negative processes.
- Binder burnout, volatile gases removed, phase transformations, pore and grain growth and/or reduction occur during ceramic firing.
- Another very important factor is the micro-and macro- heterogeneity of the initial ceramic mass. Even "pure" kaolin has many accompanying impurities.
- Artificial one-component raw materials that are used for advanced (engineering) ceramics also have inhomogeneities in grain size, forming density, and micro chemical impurities.
- the general purpose of ceramic processing is to provide a thermal stream, which should maximally (spatially and temporally) be determined by the particular thermodynamics, kinetics, mechanical behavior and technical arrangement of the particular ceramic sintering and densification.
- this thermal stream acts from a flame torch and from a preheated ambient (refractory shell and air-gas mixture).
- a real thermal stream inside a ceramic body depends on the thermal conductivity of the particular ceramic mass during its heating and sintering. Phase transformations begin after some critical temperature, and other processes and densification occur during all thermal processing. These cause a change in thermal conductivity in other parts of the ceramic body during heating.
- Microwaves are invisible electromagnetic waves which are measured in megahertz, or millions of oscillations per second (MHZ). Microwave fields are reflected off metals, which they do not heat. Accordingly, metals are used for the walls of the microwave oven (furnace) cavities and microwave conduits.
- the usual 60 Hz AC power is converted into DC power and this converted power is then placed across the special microwave tube (magnetron), which in turn converts the DC power into microwave energy at the particular voltage and frequency of 0.3 to 300 GHz (300 to 300,000 MHZ) with corresponding wavelengths ranging from 1 m to 1 mm.
- the microwave energy is transmitted to the microwave oven cavity through a metal wave-guide, whose width should be less than one wavelength and greater then one-half wavelength of the microwaves.
- the entire system being electronic, has various control safety devices and feedback systems. To use the microwave furnace successfully it is necessary to take into account the danger of the invisible microwave field. That danger is a special concern in the industrial design of the conveyer kiln.
- microwave energy can provide and accelerate ceramic densification and sintering reactions.
- the use of microwave energy to process a wide variety of ceramic materials offers many new and exciting opportunities in the processing of silicates, oxides, nitrides, and carbides by sintering formed (shaped) products from either green mass or purified powder. Sintering is accomplished by chemical reactions and/or diffusion at temperatures in excess of 500° C. with a maximum in excess of 1000° C.
- Microwave heating has three special advantages over all other methods for heating all ceramic materials.
- the first is uniform and instantaneous microwave penetration and therefore uniform heating of the material body. It eliminates stresses and cracks that are caused by thermal gradients and that are a major problem of traditional external thermal processing of ceramics.
- the second special advantage is a reverse heat-front propagation from center to surface resulting in a situation in which the material center temperature is higher than the surface temperature.
- the third advantage of microwave ceramic processing is maximum energy efficiency because the ceramic body can absorb 95%-99% of the delivered microwave energy, and this energy can be converted into useful thermal-chemical energy.
- the efficiency of energy conversion depends on microwave frequency, power level, application type, cavity size, mode of energy delivery, mass volume of the sample, the number of treated ceramic physical-chemical characteristics, and sample consistency and preparation. All of these factors are theoretically adjustable, and an ideal microwave ceramic manufacturing system must be adaptive, flexible and versatile. It is necessary to determine experimentally what the appropriate adjustment should be for a particular ceramic product.
- the microwave field induces higher diffusion rates and substantially increases apparent activation energy for a sintering process as compared with conventional thermal processing. This is a result of changes in the matter-energy assumption.
- the specific influences of ceramic type, material composition, specimen preparation initial grain size, porosity distribution, the presence of water and fluxes) on the densification and sintering behavior of several ceramics have been studied in a number of works.
- Microwave energy is absorbed continuously within the material, and it increases the temperature of the material linearly up to a critical temperature (T-crit). After T-crit, which differs for different materials, the temperature rise is accelerated due to rapidly increased microwave absorption.
- Microwave ceramic thermal processing has special properties for heat delivery and thermal penetration. These properties cause a different dynamic and kinetics of the ceramic sintering and densification processes as well as other changes because of the consequences of particular physical-chemical interactions.
- P ab (W/m 3 ) is the power dissipated
- f is the frequency
- e is the dielectric constant
- E is the electric field strength
- tand is the loss tangent for the dielectric.
- s is the conductivity
- e o is the permeability of free space
- e eff is the effective relative dielectric loss factor
- p is the density
- V is the volume
- c p is the specific heat (heat capacity) of the sample.
- the increase in temperature (DT) in time, t depends on the density (p) of the sample.
- a e is the electronic
- a l is the ionic
- a o is the dipolar orientation
- a s is the space charge polarizability.
- Other dielectric materials may have one or more exclusive mechanisms. If one phenomenon acts especially strong, others may be negligible. But under some conditions all phenomena are negligible and the technological goal may be an enhancement of one phenomenon or an insertion of an additional ingredient with enlarged polarizability.
- the a i and a e phenomena act as resistive heating of solid dielectric materials with relatively high dielectric resistivity and low dielectric constant. If the material has free electrons or electron pairs (such as carbon or silicon carbide), the a e phenomenon acts exclusively.
- the second mechanism of ceramic ionic excitation results from the fact that most silicates and aluminates, which have a dielectric constant in the range of 5-15, have an anionic polarizability behavior. This is caused by the displacement of ions of opposite sign from their regular lattice sites under the influence of an applied field and also from the deformation of the electronic shells resulting from the relative displacement of the ions.
- Ceramic electronic and ionic polarizability occurs in the range of 10 9 to 10 14 Hz when existing microwave-magnetron technical systems act in the range of 300 ⁇ 10 9 to 30 ⁇ 10 12 HZ. This means that ceramic electronic and ionic excitation by microwave energy takes place when an electrical circuit phase shift corresponds to a time lag between an applied current and induced ion and/or electron vibrations and/or transport, causing current loss, energy dissipation, and the heating of the ceramic material.
- microwave induced space charge polarization a s can affect the ceramic grain densification process, which is the transport of uncharged vacancies from the pore region through the neck region to the exterior of the grain. This process may take place in a medium temperature range, where the space charge has a significant value.
- FIG. 7 is a plot of the heat capacity of perlite where curve 1 refers to the original mineral material; curve 2 pertains to the same perlite after annealing at 1000° C.; and curve 3 refers to the bloated perlite after shock heating (special thermal processing) of the initial mineral.
- Curves 1 and 3 reveal the change in heat capacity as various hydrogen forms are removed from the material samples in a temperature range from 323 K to 1350 K.
- the major effect is exothermic, which reflects the presence of a particular combination of 1-4, 6 and 7 hydrogen forms (Table 3).
- Curve 2 which shows only a gradual change in heat capacity with temperature, indicates that the material does not contain hydrogen. Shock heating of perlite causes bloating of the mineral material. Obviously, this material easily takes up water and hydration forms from the surrounding space (ambience) because of a huge porous volume and surface area.
- Hydrogen form contents could be increased by using autoclave steam treatment as shown by sample 3.
- Curve 3 of FIG. 7 shows the dip in heat capacity in the range of temperatures from about 753 K to 1073 K, which results from the endothermic effect of the OH - ions.
- Molecules, crystal, capillary, and pore absorbed hydrogen and water can be simultaneously present in ceramics up to 1200-1300 K. This is indicated by curves 1 and 3 of FIG. 7 and is illustrated by Table 3. Obviously, there are different bonds between hydrogen forms and ceramics and these bonds are stronger at the surface of the pore, cavern or canal, which corresponds with the particular ceramic lattice.
- Various forms of hydrogen have been examined by infrared spectroscopy and optical light refraction methods, and, significantly, all these forms could be ions or a source for ions if a heating process is provided.
- a number of minerals and ceramics have an alumina-silicate type lattice as typified by silica, feldspar and pegmatite, which are usual for red clay.
- This type of lattice permits the formation of a large volume of micro caverns and canals which can capture and take up water molecules and hydrogen ions.
- the likelihood of lattice hydrogen is a property of silicate ceramics
- a surface water-hydrogen absorption is possible for all types of ceramics.
- the surface area of the ceramic bulk-piece materials--and especially fly ash-- is huge.
- the surface area of bloated perlite powder is in the range of 2.3 to 5.2 m 2 /gram. This surface area is available for the capture of various forms of hydrogen.
- the equilibrium concentration of various hydrogen forms can attain about 3% of the material weight.
- H 2 O molecules which are "low-temperature or moisture and capillary water” because these water molecules can be removed at from 100° C. to 350° C. (No. 6 and No. 7 forms in Table 4).
- One ⁇ m 2 of the alumina-silica or silica lattice can take eight OH - groups.
- One gram of the material with an inner surface area of 5.2 m 2 can absorb 8 ⁇ 5.2 ⁇ 10 18 or 4.2 ⁇ 10 19 OH - groups. This is equivalent to 7 ⁇ 10 6 OH - g-mole for 1 gram of the material, or approximately 0.1% of the weight. This shows that a huge quantity of OH - groups can be captured and be present in ceramic materials.
- the surface area of ceramic powder depends on particle size and material property. This has significant practical importance, because it is not difficult to prepare the appropriate size particles or powder, and thereby facilitate the hydrogen absorption process.
- the autoclave treatment can be an instrument for an artificial hydration of the ceramic materials.
- FIG. 8 shows the total quantity of hydrogen forms inserted by the autoclave steam.
- FIG. 8 identifies maximum conditions for steam autoclave treatment of ceramic grain or powder materials. It is preferably conducted at up to about 2.45 GPa steam pressure (approximately 21 atmospheres) during a maximum of about 12 hours.
- the hydrogen forms function as microwave susceptors which respond to microwaves.
- Hydrogen forms instantaneously generate heat which increase ceramic temperature up to the critical point when certain types of ceramic material, for example alumina ceramics, starts their response employing additional coupling mechanisms.
- This method makes it possible to precisely furnish a thermal-time-schedule of the process and to obtain a uniformity of the thermal field which provides a gentle thermal impact for each surface point of a ceramic component.
- thermal aggregates (drier and kiln) are consumption equipped with two hydraulic circulation systems.
- Each circulation system is equipped with a small blow fan and a set of jet-nozzles for free-running gas/air mixture or air.
- the first circulation system provides gas-air delivery from cooling zone to the heating and firing zones, and the second circulation system provides air delivery from outside space to the cooling zone of the kiln.
- the first circulation system delivers hot gas-air mixture to the drier and then a surplus of the hot gas-air mixture is injected to the chimney.
- a part of the gas-air injection process within the thermal aggregate is provided by vertical jet-nozzles which are positioned along the thermal aggregate.
- the vertical direction of the nozzles maintain vertical uniformity of the thermal treatment of the ceramic product.
- a ratio of the length of the air current stream to the nozzle diameter is about 100-250.
- the injection jet nozzles provide mixing and circulation of the thermal aggregate inner atmosphere.
- the mixing ratio is one volume part of the gas to the following parts of air:
- some of the nozzles are directed horizontally to the product entrance of the kiln. This provides gas-air horizontal flow with a necessary ejection of the outside air which causes a lower gas-air pressure within kiln canal compared to regular atmosphere pressure.
- Firing of large-scale thick-wall ceramic items comprises a setting of a ceramic item on a car-platform or on horizontal rollers for the periodical or conveyer movement consequently into a compartment chamber or through a tunnel canal.
- the method of ceramic firing and tunnel kiln construction includes a special construction of the kiln car--FIG. 6. This car provides movement of the ceramic item in a vertical position within the tunnel kiln.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Microbiology (AREA)
- Structural Engineering (AREA)
- Biomedical Technology (AREA)
- Materials Engineering (AREA)
- Molecular Biology (AREA)
- Inorganic Chemistry (AREA)
- Biotechnology (AREA)
- Organic Chemistry (AREA)
- Analytical Chemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Biochemistry (AREA)
- Physics & Mathematics (AREA)
- Medicinal Chemistry (AREA)
- Food Science & Technology (AREA)
- Compositions Of Oxide Ceramics (AREA)
- Drying Of Solid Materials (AREA)
- Furnace Details (AREA)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/058,903 US5911941A (en) | 1997-04-10 | 1998-04-10 | Process for the preparation of thick-walled ceramic products |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US4312297P | 1997-04-10 | 1997-04-10 | |
| US09/058,903 US5911941A (en) | 1997-04-10 | 1998-04-10 | Process for the preparation of thick-walled ceramic products |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US5911941A true US5911941A (en) | 1999-06-15 |
Family
ID=21925620
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US09/058,903 Expired - Lifetime US5911941A (en) | 1997-04-10 | 1998-04-10 | Process for the preparation of thick-walled ceramic products |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US5911941A (fr) |
| EP (1) | EP1007892B1 (fr) |
| JP (1) | JP2000510434A (fr) |
| AU (1) | AU7107898A (fr) |
| DE (1) | DE69841870D1 (fr) |
| WO (1) | WO1998045654A1 (fr) |
Cited By (36)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6187255B1 (en) * | 1997-10-11 | 2001-02-13 | Indupart Glaskeramic Stahl - Und Metallbau Gmbh | Method for producing building materials |
| US6217822B1 (en) * | 1998-02-09 | 2001-04-17 | Siemens Westinghouse Power Corporation | Method of making straight fuel cell tubes |
| US6264875B1 (en) * | 1999-08-30 | 2001-07-24 | Sang-Yool Pyun | Preparation of multi-purpose magnetized and sintered ceramics |
| US6365885B1 (en) | 1999-10-18 | 2002-04-02 | The Penn State Research Foundation | Microwave processing in pure H fields and pure E fields |
| US20020197645A1 (en) * | 2000-10-03 | 2002-12-26 | Mark Martin | Methods and compositions for directed microwave chemistry |
| US20030082633A1 (en) * | 2000-10-03 | 2003-05-01 | Martin Mark T. | Directed microwave chemistry |
| US20040159335A1 (en) * | 2002-05-17 | 2004-08-19 | P.C.T. Systems, Inc. | Method and apparatus for removing organic layers |
| US20040173608A1 (en) * | 2003-02-10 | 2004-09-09 | Seccombe Donald A. | Process and system for thermally uniform materials processing |
| US20040209303A1 (en) * | 2000-10-03 | 2004-10-21 | Martin Mark T. | Methods and compositions for directed microwave chemistry |
| WO2007147158A3 (fr) * | 2006-06-16 | 2008-04-24 | Worcester Polytech Inst | Système de détection de défaut par infrarouge et méthode D'éVALUATION Des frittés métalliques |
| US7381261B1 (en) | 2006-12-21 | 2008-06-03 | United States Gypsum Company | Expanded perlite annealing process |
| US20080227690A1 (en) * | 2000-12-29 | 2008-09-18 | Advanced Inhalation Research, Inc. | Particles for inhalation having rapid release properties |
| US20090294438A1 (en) * | 2008-05-30 | 2009-12-03 | Paul Andreas Adrian | Drying Process and Apparatus For Ceramic Greenware |
| US20090294440A1 (en) * | 2008-05-30 | 2009-12-03 | Paul Andreas Adrian | System And Method For Drying Of Ceramic Greenware |
| US20100043248A1 (en) * | 2008-08-20 | 2010-02-25 | Cervoni Ronald A | Methods for drying ceramic greenware using an electrode concentrator |
| US20100107435A1 (en) * | 2008-10-31 | 2010-05-06 | Jacob George | Methods and Apparatus for Drying Ceramic Green Bodies with Microwaves |
| US20100107931A1 (en) * | 2007-03-22 | 2010-05-06 | World Minerals, Inc. | Mineral ore expansion using microwave energy |
| CN101491919B (zh) * | 2009-02-20 | 2011-02-09 | 陕西科技大学 | 一种保温隔热板的制备方法 |
| CN102603276A (zh) * | 2012-03-13 | 2012-07-25 | 中国科学院宁波材料技术与工程研究所 | 一种莫来石纤维的制备方法 |
| US20120196237A1 (en) * | 2011-01-31 | 2012-08-02 | Clint Murray | Cylindrical burner and method for making the same |
| US20130116110A1 (en) * | 2011-11-08 | 2013-05-09 | David J. Bronfenbrenner | Control of Clay Crystallite Size for Shrinkage Management |
| US20130186887A1 (en) * | 2012-01-23 | 2013-07-25 | Whirlpool Corporation | Microwave heating apparatus |
| US20130288881A1 (en) * | 2012-04-30 | 2013-10-31 | Martin Joseph Murtagh | Control of Clay Crystallite Size for Thermal Expansion Management |
| DE102013013401A1 (de) | 2013-08-02 | 2015-02-05 | Harald Benoit | Nutzung von Siliciumcarbid (Dielektrikum)als ggf. Verbrauchsmaterial zur Erwärmung dünner Materialschichten mittels Mikrowellenstrahlung |
| US9464004B2 (en) | 2011-02-28 | 2016-10-11 | Corning Incorporated | Method for manufacturing ceramic honeycombs with reduced shrinkage |
| RU2670312C1 (ru) * | 2018-01-10 | 2018-10-22 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Оренбургский государственный университет" | Способ получения функциональной керамики |
| US10299634B2 (en) | 2017-08-08 | 2019-05-28 | Clinton Reyes | Hair clippings collection system |
| CN111138190A (zh) * | 2020-01-10 | 2020-05-12 | 广东工业大学 | 一种钙钛锆石型陶瓷固化体及其制备方法和应用 |
| US11072089B2 (en) * | 2015-05-18 | 2021-07-27 | Synrocks Sa | Method for producing a dimensionally stable concrete workpiece and dimensionally stable concrete workpiece |
| CN113643840A (zh) * | 2021-10-13 | 2021-11-12 | 西安宏星电子浆料科技股份有限公司 | 同时适用于氧化铝陶瓷基板和隔离介质层的厚膜电阻浆料 |
| US20220231317A1 (en) * | 2021-01-15 | 2022-07-21 | Bloom Energy Corporation | Method of manufacturing solid oxide electrolyzer cells using a continuous furnace |
| RU2802765C1 (ru) * | 2022-10-17 | 2023-09-01 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Оренбургский государственный университет" | Способ получения функциональной керамики из природного необогащенного глинистого сырья |
| CN117359754A (zh) * | 2023-07-04 | 2024-01-09 | 广东冠星陶瓷企业有限公司 | 一种瓷砖生产用等静压干压成型系统 |
| CN118978141A (zh) * | 2024-07-11 | 2024-11-19 | 厦门大学 | 一种超高容量的低电压硬碳的合成方法及其应用 |
| US12145293B2 (en) | 2019-04-30 | 2024-11-19 | Corning Incorporated | Methods and apparatus for microwave drying of green ceramic honeycomb bodies using adjustable air flow |
| CN120943611A (zh) * | 2025-10-14 | 2025-11-14 | 大石桥市震宇耐火材料有限公司 | 一种热膨胀补偿镁钙砖及其制备工艺 |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003137662A (ja) * | 2001-10-30 | 2003-05-14 | Kyocera Corp | セラミックス焼結体の製造方法 |
| TWI398309B (zh) * | 2009-08-10 | 2013-06-11 | Univ Nat Taiwan | Treatment of incineration fly ash by microwave sintering |
| RU2469979C2 (ru) * | 2010-07-22 | 2012-12-20 | Юрий Михайлович Крутов | Способ получения пенокерамики и изделий из нее |
| CN102425942B (zh) * | 2011-11-08 | 2014-10-08 | 湖南顶立科技有限公司 | 一种微波高温气氛推板窑 |
| RU2479538C1 (ru) * | 2011-12-14 | 2013-04-20 | Юлия Алексеевна Щепочкина | Масса для производства кирпича |
| JP5848161B2 (ja) * | 2012-02-29 | 2016-01-27 | 三菱重工業株式会社 | ハニカム成形体の製造方法 |
| RU2592293C1 (ru) * | 2015-03-02 | 2016-07-20 | Федеральное государственное бюджетное научное учреждение "Федеральный исследовательский центр Институт прикладной физики Российской академии наук" | Способ спекания керамических изделий с использованием воздействия интенсивного микроволнового излучения |
| IT201700089242A1 (it) * | 2017-08-02 | 2019-02-02 | Stefano Cassani | Metodo per il controllo di qualita' di produzione di prodotti ceramici che subiscono una formatura in pressione e una successiva cottura |
| CN110394890B (zh) * | 2019-06-25 | 2021-05-11 | 厦门三航混凝土有限公司 | 一种混凝土构件浇筑质量控制方法和系统 |
| CN117091367B (zh) * | 2023-10-17 | 2024-01-30 | 潍坊春丰新材料科技有限公司 | 一种六方氮化硼回收干燥装置 |
| JP7709708B1 (ja) | 2024-03-08 | 2025-07-17 | トヨタ自動車株式会社 | 加熱装置 |
Citations (36)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3585258A (en) * | 1965-10-19 | 1971-06-15 | Melvin L Levinson | Method of firing ceramic articles utilizing microwave energy |
| US3704523A (en) * | 1970-01-14 | 1972-12-05 | Int Standard Electric Corp | Microwave dryer for ceramic articles |
| US3731036A (en) * | 1971-10-18 | 1973-05-01 | Int Standard Electric Corp | Microwave dryer equipment |
| US4045639A (en) * | 1973-01-16 | 1977-08-30 | Food Processing Systems Corporation | Continuous microwave and vacuum dryer |
| US4057702A (en) * | 1973-10-31 | 1977-11-08 | Automatisme & Technique | Process and plant for the fritting of ceramic products |
| US4147911A (en) * | 1975-08-11 | 1979-04-03 | Nippon Steel Corporation | Method for sintering refractories and an apparatus therefor |
| US4292262A (en) * | 1979-06-28 | 1981-09-29 | Tobin Jr Leo W | Ceramic material processing |
| US4298554A (en) * | 1977-11-14 | 1981-11-03 | Lebanon Steel Foundry | Coherent rigid solid material |
| US4347890A (en) * | 1981-03-09 | 1982-09-07 | Pq Corporation | Method for binding particulate materials |
| US4505787A (en) * | 1981-07-13 | 1985-03-19 | Super Fuel Systems Incorporated | Process for production of a carbide by-product with microwave energy and aluminum by electrolysis |
| US4687895A (en) * | 1984-07-30 | 1987-08-18 | Superwave Technology, Inc. | Conveyorized microwave heating system |
| US4771153A (en) * | 1986-02-21 | 1988-09-13 | Kabushiki Kaisha Toyota Cho Kenkyusho | Apparatus for microwave heating of ceramic |
| US4880578A (en) * | 1988-08-08 | 1989-11-14 | The United States Of America As Represented By The United States Department Of Energy | Method for heat treating and sintering metal oxides with microwave radiation |
| US4963709A (en) * | 1987-07-24 | 1990-10-16 | The United States Of America As Represented By The Department Of Energy | Method and device for microwave sintering large ceramic articles |
| US5010220A (en) * | 1988-02-16 | 1991-04-23 | Alcan International Limited | Process and apparatus for heating bodies at high temperature and pressure utilizing microwave energy |
| US5072087A (en) * | 1988-10-06 | 1991-12-10 | Alcan International Limited | Process for heating materials by microwave energy |
| US5077268A (en) * | 1988-04-05 | 1991-12-31 | University Of Florida | Procesing of superconducting ceramics using microwave energy |
| US5108670A (en) * | 1990-04-20 | 1992-04-28 | Martin Marietta Energy Systems, Inc. | Process for making a titanium diboride-chromium diboride-yttrium titanium oxide ceramic composition |
| US5122633A (en) * | 1989-06-07 | 1992-06-16 | Wolfgang Moshammer | Method and apparatus for radiation microwave energy into material containing water or mixed with water |
| US5164130A (en) * | 1990-04-20 | 1992-11-17 | Martin Marietta Energy Systems, Inc. | Method of sintering ceramic materials |
| US5202541A (en) * | 1991-01-28 | 1993-04-13 | Alcan International Limited | Microwave heating of workpieces |
| US5223186A (en) * | 1991-04-15 | 1993-06-29 | The United States Of America As Represented By The United States Department Of Energy | Microwave sintering of nanophase ceramics without concomitant grain growth |
| US5227600A (en) * | 1992-07-31 | 1993-07-13 | The United States Of America As Represented By The United States Department Of Energy | Microwave sintering of multiple articles |
| US5252267A (en) * | 1993-03-18 | 1993-10-12 | Holcombe Cressie E | Process for microwave sintering boron carbide |
| US5266762A (en) * | 1992-11-04 | 1993-11-30 | Martin Marietta Energy Systems, Inc. | Method and apparatus for radio frequency ceramic sintering |
| US5294763A (en) * | 1989-04-07 | 1994-03-15 | Minnesota Mining And Manufacturing Company | Microwave heatable composites |
| US5321223A (en) * | 1991-10-23 | 1994-06-14 | Martin Marietta Energy Systems, Inc. | Method of sintering materials with microwave radiation |
| US5365042A (en) * | 1991-03-14 | 1994-11-15 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "S.N.E.C.M.A." | Installation and method for heat treating parts made of a composite material having a ceramic matrix by using microwave energy |
| US5408074A (en) * | 1991-11-05 | 1995-04-18 | Oscar Gossler Kg (Gmbh & Co.) | Apparatus for the selective control of heating and irradiation of materials in a conveying path |
| US5410135A (en) * | 1988-09-01 | 1995-04-25 | James River Paper Company, Inc. | Self limiting microwave heaters |
| US5432325A (en) * | 1994-10-20 | 1995-07-11 | University Of California | Microwave sintering of single plate-shaped articles |
| US5466917A (en) * | 1991-06-05 | 1995-11-14 | Kabushiki Kaisha Kouransha | Microwave-absorptive heat-generating body and method for forming a heat-generating layer in a microwave-absorptive heat-generating body |
| US5507986A (en) * | 1993-05-13 | 1996-04-16 | The Babcock & Wilcox Company | Method of making a ceramic tube |
| US5521360A (en) * | 1994-09-14 | 1996-05-28 | Martin Marietta Energy Systems, Inc. | Apparatus and method for microwave processing of materials |
| GB2296173A (en) * | 1993-08-10 | 1996-06-19 | Ea Tech Ltd | Microwave-assisted processingn of materials |
| US5538681A (en) * | 1994-09-12 | 1996-07-23 | Corning Incorporated | Drying process to produce crack-free bodies |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| IT1100344B (it) * | 1978-11-23 | 1985-09-28 | Welko Ind Spa | Forno a rulli incorporante un canale di essiccazione,particolarmente per materiali ceramici o refrattari |
| AU7092981A (en) * | 1980-05-30 | 1981-12-03 | Elektro-Dahlen A.B. | Baking oven and cart with rotating surfaces |
| US4319410A (en) * | 1980-06-24 | 1982-03-16 | The Brandt Company | Dryer system for drilling mud cuttings |
| DE3205076A1 (de) * | 1981-02-13 | 1982-11-25 | Kurosaki Refractories Co., Ltd., Kitakyushu, Fukuoka | Verfahren zum herstellen eines giessduesenpresslings und materialzusammensetzung dafuer |
| US4338135A (en) * | 1981-04-06 | 1982-07-06 | Texas Industries, Inc. | Microwave curing of cementitious material |
| JPH0657842B2 (ja) * | 1985-02-28 | 1994-08-03 | 株式会社井上ジャパックス研究所 | 粉末焼結法 |
| US4935178A (en) * | 1986-06-24 | 1990-06-19 | General Signal Corporation | Method of making refractory fiber products |
-
1998
- 1998-04-10 EP EP98918089A patent/EP1007892B1/fr not_active Expired - Lifetime
- 1998-04-10 WO PCT/US1998/007198 patent/WO1998045654A1/fr not_active Ceased
- 1998-04-10 DE DE69841870T patent/DE69841870D1/de not_active Expired - Lifetime
- 1998-04-10 US US09/058,903 patent/US5911941A/en not_active Expired - Lifetime
- 1998-04-10 JP JP10543151A patent/JP2000510434A/ja active Pending
- 1998-04-10 AU AU71078/98A patent/AU7107898A/en not_active Abandoned
Patent Citations (36)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3585258A (en) * | 1965-10-19 | 1971-06-15 | Melvin L Levinson | Method of firing ceramic articles utilizing microwave energy |
| US3704523A (en) * | 1970-01-14 | 1972-12-05 | Int Standard Electric Corp | Microwave dryer for ceramic articles |
| US3731036A (en) * | 1971-10-18 | 1973-05-01 | Int Standard Electric Corp | Microwave dryer equipment |
| US4045639A (en) * | 1973-01-16 | 1977-08-30 | Food Processing Systems Corporation | Continuous microwave and vacuum dryer |
| US4057702A (en) * | 1973-10-31 | 1977-11-08 | Automatisme & Technique | Process and plant for the fritting of ceramic products |
| US4147911A (en) * | 1975-08-11 | 1979-04-03 | Nippon Steel Corporation | Method for sintering refractories and an apparatus therefor |
| US4298554A (en) * | 1977-11-14 | 1981-11-03 | Lebanon Steel Foundry | Coherent rigid solid material |
| US4292262A (en) * | 1979-06-28 | 1981-09-29 | Tobin Jr Leo W | Ceramic material processing |
| US4347890A (en) * | 1981-03-09 | 1982-09-07 | Pq Corporation | Method for binding particulate materials |
| US4505787A (en) * | 1981-07-13 | 1985-03-19 | Super Fuel Systems Incorporated | Process for production of a carbide by-product with microwave energy and aluminum by electrolysis |
| US4687895A (en) * | 1984-07-30 | 1987-08-18 | Superwave Technology, Inc. | Conveyorized microwave heating system |
| US4771153A (en) * | 1986-02-21 | 1988-09-13 | Kabushiki Kaisha Toyota Cho Kenkyusho | Apparatus for microwave heating of ceramic |
| US4963709A (en) * | 1987-07-24 | 1990-10-16 | The United States Of America As Represented By The Department Of Energy | Method and device for microwave sintering large ceramic articles |
| US5010220A (en) * | 1988-02-16 | 1991-04-23 | Alcan International Limited | Process and apparatus for heating bodies at high temperature and pressure utilizing microwave energy |
| US5077268A (en) * | 1988-04-05 | 1991-12-31 | University Of Florida | Procesing of superconducting ceramics using microwave energy |
| US4880578A (en) * | 1988-08-08 | 1989-11-14 | The United States Of America As Represented By The United States Department Of Energy | Method for heat treating and sintering metal oxides with microwave radiation |
| US5410135A (en) * | 1988-09-01 | 1995-04-25 | James River Paper Company, Inc. | Self limiting microwave heaters |
| US5072087A (en) * | 1988-10-06 | 1991-12-10 | Alcan International Limited | Process for heating materials by microwave energy |
| US5294763A (en) * | 1989-04-07 | 1994-03-15 | Minnesota Mining And Manufacturing Company | Microwave heatable composites |
| US5122633A (en) * | 1989-06-07 | 1992-06-16 | Wolfgang Moshammer | Method and apparatus for radiation microwave energy into material containing water or mixed with water |
| US5108670A (en) * | 1990-04-20 | 1992-04-28 | Martin Marietta Energy Systems, Inc. | Process for making a titanium diboride-chromium diboride-yttrium titanium oxide ceramic composition |
| US5164130A (en) * | 1990-04-20 | 1992-11-17 | Martin Marietta Energy Systems, Inc. | Method of sintering ceramic materials |
| US5202541A (en) * | 1991-01-28 | 1993-04-13 | Alcan International Limited | Microwave heating of workpieces |
| US5365042A (en) * | 1991-03-14 | 1994-11-15 | Societe Nationale D'etude Et De Construction De Moteurs D'aviation "S.N.E.C.M.A." | Installation and method for heat treating parts made of a composite material having a ceramic matrix by using microwave energy |
| US5223186A (en) * | 1991-04-15 | 1993-06-29 | The United States Of America As Represented By The United States Department Of Energy | Microwave sintering of nanophase ceramics without concomitant grain growth |
| US5466917A (en) * | 1991-06-05 | 1995-11-14 | Kabushiki Kaisha Kouransha | Microwave-absorptive heat-generating body and method for forming a heat-generating layer in a microwave-absorptive heat-generating body |
| US5321223A (en) * | 1991-10-23 | 1994-06-14 | Martin Marietta Energy Systems, Inc. | Method of sintering materials with microwave radiation |
| US5408074A (en) * | 1991-11-05 | 1995-04-18 | Oscar Gossler Kg (Gmbh & Co.) | Apparatus for the selective control of heating and irradiation of materials in a conveying path |
| US5227600A (en) * | 1992-07-31 | 1993-07-13 | The United States Of America As Represented By The United States Department Of Energy | Microwave sintering of multiple articles |
| US5266762A (en) * | 1992-11-04 | 1993-11-30 | Martin Marietta Energy Systems, Inc. | Method and apparatus for radio frequency ceramic sintering |
| US5252267A (en) * | 1993-03-18 | 1993-10-12 | Holcombe Cressie E | Process for microwave sintering boron carbide |
| US5507986A (en) * | 1993-05-13 | 1996-04-16 | The Babcock & Wilcox Company | Method of making a ceramic tube |
| GB2296173A (en) * | 1993-08-10 | 1996-06-19 | Ea Tech Ltd | Microwave-assisted processingn of materials |
| US5538681A (en) * | 1994-09-12 | 1996-07-23 | Corning Incorporated | Drying process to produce crack-free bodies |
| US5521360A (en) * | 1994-09-14 | 1996-05-28 | Martin Marietta Energy Systems, Inc. | Apparatus and method for microwave processing of materials |
| US5432325A (en) * | 1994-10-20 | 1995-07-11 | University Of California | Microwave sintering of single plate-shaped articles |
Non-Patent Citations (50)
| Title |
|---|
| American Ceramic Society Bulletin, vol. 75, No. 9, Sep. 1996, p. 34. * |
| FCR Wroe; "Scaling Up the Microwave Firing of Ceramics"; Microwaves II; pp. 449-465 (No Date). |
| FCR Wroe; Scaling Up the Microwave Firing of Ceramics ; Microwaves II; pp. 449 465 (No Date). * |
| I Ahmad, R. Dalton, and D. Clark; "Unique Application of Microwave Energy to the Processing of Ceramic Materials"; Journal of Microwave Power & Electromagnetic Energy; vol. 26 No. 3, 1991, pp. 128-138, 1991. |
| I Ahmad, R. Dalton, and D. Clark; Unique Application of Microwave Energy to the Processing of Ceramic Materials ; Journal of Microwave Power & Electromagnetic Energy; vol. 26 No. 3, 1991, pp. 128 138, 1991. * |
| Internet Printout of "2.6 Production of SiC Fibre Toughened Glass and Glass-Ceramic Matrix Composites" (No Date). |
| Internet Printout of "AEE-Magnesium Aluminate, Spinel MgAl204 142" (No Date). |
| Internet Printout of "AEE-Mullite 3AL203" (No Date). |
| Internet Printout of "Equation of State of MgAl-20-4-Spinel" No Date. |
| Internet Printout of "First Single-Crystal Mullite Fibers" (No Date). |
| Internet Printout of "Glaze & Clay Tutorial-2" (No Date). |
| Internet Printout of "How Things Work--Microwave Ovens" (No Date). |
| Internet Printout of "Microwave Induced Combustion Synthesis of Ceramic and Ceramic-Metal Composites" Apr. 1995. |
| Internet Printout of 2.6 Production of SiC Fibre Toughened Glass and Glass Ceramic Matrix Composites (No Date). * |
| Internet Printout of 5th Microwave and HF Conference (No Date). * |
| Internet Printout of A Leader in the Design and Manufacture of Microwave and RF Filters (No Date). * |
| Internet Printout of AEE Magnesium Aluminate, Spinel MgAl204 142 (No Date). * |
| Internet Printout of AEE Mullite 3AL203 (No Date). * |
| Internet Printout of Ceramics & Ceramic Composites 1995. * |
| Internet Printout of Ceramics and Ceramic Composites (No Date). * |
| Internet Printout of Chemical Preparation Methods for Ceramic Powders (No Date). * |
| Internet Printout of Energy Efficiency and Renewable Energy Program (No Date). * |
| Internet Printout of Equation of State of MgAl 20 4 Spinel No Date. * |
| Internet Printout of First Single Crystal Mullite Fibers (No Date). * |
| Internet Printout of Glaze & Clay Tutorial 2 (No Date). * |
| Internet Printout of How Things Work Microwave Ovens (No Date). * |
| Internet Printout of KCM 73 Sintered Mullite (No Date). * |
| Internet Printout of KCM White Fused Mullite (No Date). * |
| Internet Printout of Microwave Chemistry (No Date). * |
| Internet Printout of Microwave Firing Equipment (No Date). * |
| Internet Printout of Microwave Furnace Development (No Date). * |
| Internet Printout of Microwave Induced Combustion Synthesis of Ceramic and Ceramic Metal Composites Apr. 1995. * |
| Internet Printout of Microwave Processing Group (No Date). * |
| Internet Printout of Microwave Processing of Ceramics (No Date). * |
| Internet Printout of Microwave Processing of Ceramics 1995. * |
| Internet Printout of The Mineral Spinel (No Date). * |
| Internet Printout of Variable Frequency Microwave Furnace System (No Date). * |
| Internet Search Printout of Synonyms of Minerals (No Date). * |
| Keith Wilfinger; "Ceramic Package Fabrication for YMP Nuclear Waste Disposal"; Lawrence Livermore Natl Lab; pp. 1-32, Aug. 1994. |
| Keith Wilfinger; Ceramic Package Fabrication for YMP Nuclear Waste Disposal ; Lawrence Livermore Natl Lab; pp. 1 32, Aug. 1994. * |
| Kirk Othmer Encyclopedia of Chemical Technology; Ceramics ; vol. 5; pp. 599 639 (No Date). * |
| Kirk Othmer Encyclopedia of Chemical Technology; Microwave Technology ; vol. 16; pp. 672 679, 694, 700 (No Date). * |
| Kirk-Othmer Encyclopedia of Chemical Technology; "Ceramics"; vol. 5; pp. 599-639 (No Date). |
| Kirk-Othmer Encyclopedia of Chemical Technology; "Microwave Technology"; vol. 16; pp. 672-679, 694, 700 (No Date). |
| Kurte Slekafus; "The Remarkable Radiation Resistance of the Oxide Spinel"; Los Alamos Natl Lab; Sep. 1995. |
| Kurte Slekafus; The Remarkable Radiation Resistance of the Oxide Spinel ; Los Alamos Natl Lab; Sep. 1995. * |
| Richard L Lehman; "Overview of Ceramic Design and Process Engineering"; ASM International; (No Date). |
| Richard L Lehman; Overview of Ceramic Design and Process Engineering ; ASM International; (No Date). * |
| Willard H. Sutton; "Microwave Processing of Ceramic Materials"; Ceramic Bulletin vol. 68 No. 2 1989; pp. 376-385, 1989. |
| Willard H. Sutton; Microwave Processing of Ceramic Materials ; Ceramic Bulletin vol. 68 No. 2 1989; pp. 376 385, 1989. * |
Cited By (60)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6187255B1 (en) * | 1997-10-11 | 2001-02-13 | Indupart Glaskeramic Stahl - Und Metallbau Gmbh | Method for producing building materials |
| US6217822B1 (en) * | 1998-02-09 | 2001-04-17 | Siemens Westinghouse Power Corporation | Method of making straight fuel cell tubes |
| US6264875B1 (en) * | 1999-08-30 | 2001-07-24 | Sang-Yool Pyun | Preparation of multi-purpose magnetized and sintered ceramics |
| US6365885B1 (en) | 1999-10-18 | 2002-04-02 | The Penn State Research Foundation | Microwave processing in pure H fields and pure E fields |
| US20020197645A1 (en) * | 2000-10-03 | 2002-12-26 | Mark Martin | Methods and compositions for directed microwave chemistry |
| US20030082633A1 (en) * | 2000-10-03 | 2003-05-01 | Martin Mark T. | Directed microwave chemistry |
| US20040209303A1 (en) * | 2000-10-03 | 2004-10-21 | Martin Mark T. | Methods and compositions for directed microwave chemistry |
| US7718445B2 (en) | 2000-10-03 | 2010-05-18 | Mirari Biosciences, Inc. | Methods and compositions for directed microwave chemistry |
| US20050191708A1 (en) * | 2000-10-03 | 2005-09-01 | Mirari Biosciences, Inc. | Microwave microfluidics |
| US8309367B2 (en) | 2000-10-03 | 2012-11-13 | Mirari Biosciences, Inc. | Microwave microfluidics |
| US7348182B2 (en) | 2000-10-03 | 2008-03-25 | Mirari Biosciences, Inc. | Directed microwave chemistry |
| US7351590B2 (en) | 2000-10-03 | 2008-04-01 | Mirari Biosciences, Inc. | Methods and compositions for directed microwave chemistry |
| US8431414B2 (en) | 2000-10-03 | 2013-04-30 | Mirari Biosciences, Inc. | Methods and compositions for directed microwave chemistry |
| US20080248489A1 (en) * | 2000-10-03 | 2008-10-09 | Mark Martin | Methods and compositions for directed microwave chemistry |
| US20080227690A1 (en) * | 2000-12-29 | 2008-09-18 | Advanced Inhalation Research, Inc. | Particles for inhalation having rapid release properties |
| US20040159335A1 (en) * | 2002-05-17 | 2004-08-19 | P.C.T. Systems, Inc. | Method and apparatus for removing organic layers |
| WO2004023144A1 (fr) * | 2002-09-05 | 2004-03-18 | Mirari Biosciences, Inc. | Chimie dirigee par energie micro-ondes |
| WO2004073037A3 (fr) * | 2003-02-10 | 2005-04-21 | Btu Int | Procede et systeme permettant de traiter des materiaux thermiquement uniformes |
| US7196297B2 (en) * | 2003-02-10 | 2007-03-27 | Btu International, Inc. | Process and system for thermally uniform materials processing |
| US20040173608A1 (en) * | 2003-02-10 | 2004-09-09 | Seccombe Donald A. | Process and system for thermally uniform materials processing |
| US8581975B2 (en) | 2006-06-16 | 2013-11-12 | Worcester Polytechnic Institute | Infrared defect detection system and method for the evaluation of powdermetallic compacts |
| WO2007147158A3 (fr) * | 2006-06-16 | 2008-04-24 | Worcester Polytech Inst | Système de détection de défaut par infrarouge et méthode D'éVALUATION Des frittés métalliques |
| US20100033565A1 (en) * | 2006-06-16 | 2010-02-11 | Worcester Polytechnic Institute | Infrared Defect Detection System and Method for the Evaluation of Powdermetallic Compacts |
| US7381261B1 (en) | 2006-12-21 | 2008-06-03 | United States Gypsum Company | Expanded perlite annealing process |
| US20100107931A1 (en) * | 2007-03-22 | 2010-05-06 | World Minerals, Inc. | Mineral ore expansion using microwave energy |
| US20090294440A1 (en) * | 2008-05-30 | 2009-12-03 | Paul Andreas Adrian | System And Method For Drying Of Ceramic Greenware |
| US20090294438A1 (en) * | 2008-05-30 | 2009-12-03 | Paul Andreas Adrian | Drying Process and Apparatus For Ceramic Greenware |
| US9239188B2 (en) * | 2008-05-30 | 2016-01-19 | Corning Incorporated | System and method for drying of ceramic greenware |
| US8729436B2 (en) * | 2008-05-30 | 2014-05-20 | Corning Incorporated | Drying process and apparatus for ceramic greenware |
| WO2010021679A1 (fr) * | 2008-08-20 | 2010-02-25 | Corning Incorporated | Procédés de séchage d'une pièce crue en céramique à l'aide d'un concentrateur d'électrode |
| US9545735B2 (en) * | 2008-08-20 | 2017-01-17 | Corning Incorporated | Methods for drying ceramic greenware using an electrode concentrator |
| US20100043248A1 (en) * | 2008-08-20 | 2010-02-25 | Cervoni Ronald A | Methods for drying ceramic greenware using an electrode concentrator |
| US20100107435A1 (en) * | 2008-10-31 | 2010-05-06 | Jacob George | Methods and Apparatus for Drying Ceramic Green Bodies with Microwaves |
| US8020314B2 (en) * | 2008-10-31 | 2011-09-20 | Corning Incorporated | Methods and apparatus for drying ceramic green bodies with microwaves |
| CN101491919B (zh) * | 2009-02-20 | 2011-02-09 | 陕西科技大学 | 一种保温隔热板的制备方法 |
| US20120196237A1 (en) * | 2011-01-31 | 2012-08-02 | Clint Murray | Cylindrical burner and method for making the same |
| US9464004B2 (en) | 2011-02-28 | 2016-10-11 | Corning Incorporated | Method for manufacturing ceramic honeycombs with reduced shrinkage |
| US20130116110A1 (en) * | 2011-11-08 | 2013-05-09 | David J. Bronfenbrenner | Control of Clay Crystallite Size for Shrinkage Management |
| US8765049B2 (en) * | 2011-11-08 | 2014-07-01 | Corning Incorporated | Control of clay crystallite size for shrinkage management |
| US20130186887A1 (en) * | 2012-01-23 | 2013-07-25 | Whirlpool Corporation | Microwave heating apparatus |
| US10271388B2 (en) * | 2012-01-23 | 2019-04-23 | Whirlpool Corporation | Microwave heating apparatus |
| US11395380B2 (en) * | 2012-01-23 | 2022-07-19 | Whirlpool Corporation | Method of heating a load in a cavity using microwaves |
| CN102603276A (zh) * | 2012-03-13 | 2012-07-25 | 中国科学院宁波材料技术与工程研究所 | 一种莫来石纤维的制备方法 |
| CN104718174A (zh) * | 2012-04-30 | 2015-06-17 | 康宁股份有限公司 | 用于热膨胀管理的粘土微晶尺寸控制 |
| US8758671B2 (en) * | 2012-04-30 | 2014-06-24 | Corning Incorporated | Control of clay crystallite size for thermal expansion management |
| US20130288881A1 (en) * | 2012-04-30 | 2013-10-31 | Martin Joseph Murtagh | Control of Clay Crystallite Size for Thermal Expansion Management |
| DE102013013401A1 (de) | 2013-08-02 | 2015-02-05 | Harald Benoit | Nutzung von Siliciumcarbid (Dielektrikum)als ggf. Verbrauchsmaterial zur Erwärmung dünner Materialschichten mittels Mikrowellenstrahlung |
| US11072089B2 (en) * | 2015-05-18 | 2021-07-27 | Synrocks Sa | Method for producing a dimensionally stable concrete workpiece and dimensionally stable concrete workpiece |
| US10299634B2 (en) | 2017-08-08 | 2019-05-28 | Clinton Reyes | Hair clippings collection system |
| RU2670312C1 (ru) * | 2018-01-10 | 2018-10-22 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Оренбургский государственный университет" | Способ получения функциональной керамики |
| US12145293B2 (en) | 2019-04-30 | 2024-11-19 | Corning Incorporated | Methods and apparatus for microwave drying of green ceramic honeycomb bodies using adjustable air flow |
| CN111138190A (zh) * | 2020-01-10 | 2020-05-12 | 广东工业大学 | 一种钙钛锆石型陶瓷固化体及其制备方法和应用 |
| US20220231317A1 (en) * | 2021-01-15 | 2022-07-21 | Bloom Energy Corporation | Method of manufacturing solid oxide electrolyzer cells using a continuous furnace |
| CN113643840B (zh) * | 2021-10-13 | 2022-03-11 | 西安宏星电子浆料科技股份有限公司 | 同时适用于氧化铝陶瓷基板和隔离介质层的厚膜电阻浆料 |
| CN113643840A (zh) * | 2021-10-13 | 2021-11-12 | 西安宏星电子浆料科技股份有限公司 | 同时适用于氧化铝陶瓷基板和隔离介质层的厚膜电阻浆料 |
| RU2802765C1 (ru) * | 2022-10-17 | 2023-09-01 | Федеральное государственное бюджетное образовательное учреждение высшего образования "Оренбургский государственный университет" | Способ получения функциональной керамики из природного необогащенного глинистого сырья |
| CN117359754A (zh) * | 2023-07-04 | 2024-01-09 | 广东冠星陶瓷企业有限公司 | 一种瓷砖生产用等静压干压成型系统 |
| CN117359754B (zh) * | 2023-07-04 | 2024-04-02 | 广东冠星陶瓷企业有限公司 | 一种瓷砖生产用等静压干压成型系统 |
| CN118978141A (zh) * | 2024-07-11 | 2024-11-19 | 厦门大学 | 一种超高容量的低电压硬碳的合成方法及其应用 |
| CN120943611A (zh) * | 2025-10-14 | 2025-11-14 | 大石桥市震宇耐火材料有限公司 | 一种热膨胀补偿镁钙砖及其制备工艺 |
Also Published As
| Publication number | Publication date |
|---|---|
| AU7107898A (en) | 1998-10-30 |
| EP1007892A4 (fr) | 2004-07-07 |
| EP1007892B1 (fr) | 2010-09-01 |
| EP1007892A1 (fr) | 2000-06-14 |
| JP2000510434A (ja) | 2000-08-15 |
| DE69841870D1 (de) | 2010-10-14 |
| WO1998045654A1 (fr) | 1998-10-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5911941A (en) | Process for the preparation of thick-walled ceramic products | |
| WO1998045654A9 (fr) | Procede et appareil pour la preparation de produits en ceramique a paroi epaisse | |
| Taurino et al. | New ceramic materials from MSWI bottom ash obtained by an innovative microwave-assisted sintering process | |
| Tarhan | Usage of fired wall tile wastes into fireclay sanitaryware products | |
| Boccaccini et al. | Microwave processing of glass matrix composites containing controlled isolated porosity | |
| Bodhak et al. | Densification Study and Mechanical Properties of Microwave‐Sintered Mullite and Mullite–Zirconia Composites | |
| Shmuradko et al. | Composition, structure, and property formation of heat insulation fire-and heat-reflecting materials based on vermiculite for industrial power generation | |
| Obada et al. | Physical and mechanical properties of porous kaolin based ceramics at different sintering temperatures | |
| Rakhila et al. | Synthesis and characterization of a red clay based new composite ceramic material | |
| KR950701301A (ko) | 세라믹물과 그 제조방법 | |
| Clark et al. | Recent developments in the microwave processing of ceramics | |
| Ho et al. | Characteristics of porous ceramics prepared from sandblasting waste and waste diatomite by co‐sintering process | |
| CN109437755A (zh) | 预制板及其制备方法和应用 | |
| Ercioglu et al. | An environmentally friendly process for preparing commercial ceramic foam composites based on frit/glass wastes | |
| Zhu et al. | Preparation of castable foam with regular micro-spherical pore structure as a substitute for diatomite brick | |
| Paunescu et al. | Thermal insulating material with high mechanical strength made from clay brick waste and coal ash using the microwave energy | |
| Sadik et al. | Characterization of elaborated Moroccan mullite to improving porous refractories quality | |
| Ali et al. | Mutations in burnt-clay brick properties attributable to waste glass | |
| Santos et al. | Global insight into microwave stoneware firing: Macro and microstructural changes | |
| Darweesh | Gradual glass waste replacement at the expense of feldspar in Ceramic tiles | |
| Salvini et al. | Designing insulating ceramic foams for high temperature furnace lining | |
| Asante-Kyei et al. | Developing Recipe from Local Ceramic Raw Materials for Making Crucibles in Ghana | |
| JP3231197B2 (ja) | 廃棄物を原料とするセラミックスの製造方法およびセラミックス焼成炉 | |
| JP4630111B2 (ja) | 耐火物、その製造方法、および、加熱炉 | |
| Ajayi et al. | DEVELOPMENT OF AN ELECTRIC FURNACE USING BENTONITE AND KAOLIN SODIUM SILICATE AS REFRACTORY MATERIAL |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: NUCON SYSTEMS, NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:ROKHVARGER, ANATOLY E.;KHIZH, ADAM B.;REEL/FRAME:009118/0940 Effective date: 19980407 |
|
| STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
| AS | Assignment |
Owner name: ADVANCED CERAMIC TECHNOLOGIES, INC., NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:ROKHVARGER, ANATOLY;REEL/FRAME:011260/0768 Effective date: 20000426 |
|
| FPAY | Fee payment |
Year of fee payment: 4 |
|
| REMI | Maintenance fee reminder mailed | ||
| FEPP | Fee payment procedure |
Free format text: PAT HOLDER NO LONGER CLAIMS SMALL ENTITY STATUS, ENTITY STATUS SET TO UNDISCOUNTED (ORIGINAL EVENT CODE: STOL); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
| FPAY | Fee payment |
Year of fee payment: 8 |
|
| AS | Assignment |
Owner name: ROKON SYSTEMS, INC., NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:NUCON SYSTEMS, INC.;REEL/FRAME:025192/0676 Effective date: 20101021 |
|
| REMI | Maintenance fee reminder mailed | ||
| FPAY | Fee payment |
Year of fee payment: 12 |
|
| SULP | Surcharge for late payment |
Year of fee payment: 11 |